bfd/
[binutils.git] / bfd / elflink.c
blob984e8282b8f6be3fd58fd705b6f56cc4aea33a1f
1 /* ELF linking support for BFD.
2 Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
3 2005, 2006 Free Software Foundation, Inc.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
21 #include "bfd.h"
22 #include "sysdep.h"
23 #include "bfdlink.h"
24 #include "libbfd.h"
25 #define ARCH_SIZE 0
26 #include "elf-bfd.h"
27 #include "safe-ctype.h"
28 #include "libiberty.h"
29 #include "objalloc.h"
31 /* Define a symbol in a dynamic linkage section. */
33 struct elf_link_hash_entry *
34 _bfd_elf_define_linkage_sym (bfd *abfd,
35 struct bfd_link_info *info,
36 asection *sec,
37 const char *name)
39 struct elf_link_hash_entry *h;
40 struct bfd_link_hash_entry *bh;
41 const struct elf_backend_data *bed;
43 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
44 if (h != NULL)
46 /* Zap symbol defined in an as-needed lib that wasn't linked.
47 This is a symptom of a larger problem: Absolute symbols
48 defined in shared libraries can't be overridden, because we
49 lose the link to the bfd which is via the symbol section. */
50 h->root.type = bfd_link_hash_new;
53 bh = &h->root;
54 if (!_bfd_generic_link_add_one_symbol (info, abfd, name, BSF_GLOBAL,
55 sec, 0, NULL, FALSE,
56 get_elf_backend_data (abfd)->collect,
57 &bh))
58 return NULL;
59 h = (struct elf_link_hash_entry *) bh;
60 h->def_regular = 1;
61 h->type = STT_OBJECT;
62 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
64 bed = get_elf_backend_data (abfd);
65 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
66 return h;
69 bfd_boolean
70 _bfd_elf_create_got_section (bfd *abfd, struct bfd_link_info *info)
72 flagword flags;
73 asection *s;
74 struct elf_link_hash_entry *h;
75 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
76 int ptralign;
78 /* This function may be called more than once. */
79 s = bfd_get_section_by_name (abfd, ".got");
80 if (s != NULL && (s->flags & SEC_LINKER_CREATED) != 0)
81 return TRUE;
83 switch (bed->s->arch_size)
85 case 32:
86 ptralign = 2;
87 break;
89 case 64:
90 ptralign = 3;
91 break;
93 default:
94 bfd_set_error (bfd_error_bad_value);
95 return FALSE;
98 flags = bed->dynamic_sec_flags;
100 s = bfd_make_section_with_flags (abfd, ".got", flags);
101 if (s == NULL
102 || !bfd_set_section_alignment (abfd, s, ptralign))
103 return FALSE;
105 if (bed->want_got_plt)
107 s = bfd_make_section_with_flags (abfd, ".got.plt", flags);
108 if (s == NULL
109 || !bfd_set_section_alignment (abfd, s, ptralign))
110 return FALSE;
113 if (bed->want_got_sym)
115 /* Define the symbol _GLOBAL_OFFSET_TABLE_ at the start of the .got
116 (or .got.plt) section. We don't do this in the linker script
117 because we don't want to define the symbol if we are not creating
118 a global offset table. */
119 h = _bfd_elf_define_linkage_sym (abfd, info, s, "_GLOBAL_OFFSET_TABLE_");
120 elf_hash_table (info)->hgot = h;
121 if (h == NULL)
122 return FALSE;
125 /* The first bit of the global offset table is the header. */
126 s->size += bed->got_header_size;
128 return TRUE;
131 /* Create a strtab to hold the dynamic symbol names. */
132 static bfd_boolean
133 _bfd_elf_link_create_dynstrtab (bfd *abfd, struct bfd_link_info *info)
135 struct elf_link_hash_table *hash_table;
137 hash_table = elf_hash_table (info);
138 if (hash_table->dynobj == NULL)
139 hash_table->dynobj = abfd;
141 if (hash_table->dynstr == NULL)
143 hash_table->dynstr = _bfd_elf_strtab_init ();
144 if (hash_table->dynstr == NULL)
145 return FALSE;
147 return TRUE;
150 /* Create some sections which will be filled in with dynamic linking
151 information. ABFD is an input file which requires dynamic sections
152 to be created. The dynamic sections take up virtual memory space
153 when the final executable is run, so we need to create them before
154 addresses are assigned to the output sections. We work out the
155 actual contents and size of these sections later. */
157 bfd_boolean
158 _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
160 flagword flags;
161 register asection *s;
162 const struct elf_backend_data *bed;
164 if (! is_elf_hash_table (info->hash))
165 return FALSE;
167 if (elf_hash_table (info)->dynamic_sections_created)
168 return TRUE;
170 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
171 return FALSE;
173 abfd = elf_hash_table (info)->dynobj;
174 bed = get_elf_backend_data (abfd);
176 flags = bed->dynamic_sec_flags;
178 /* A dynamically linked executable has a .interp section, but a
179 shared library does not. */
180 if (info->executable)
182 s = bfd_make_section_with_flags (abfd, ".interp",
183 flags | SEC_READONLY);
184 if (s == NULL)
185 return FALSE;
188 if (! info->traditional_format)
190 s = bfd_make_section_with_flags (abfd, ".eh_frame_hdr",
191 flags | SEC_READONLY);
192 if (s == NULL
193 || ! bfd_set_section_alignment (abfd, s, 2))
194 return FALSE;
195 elf_hash_table (info)->eh_info.hdr_sec = s;
198 /* Create sections to hold version informations. These are removed
199 if they are not needed. */
200 s = bfd_make_section_with_flags (abfd, ".gnu.version_d",
201 flags | SEC_READONLY);
202 if (s == NULL
203 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
204 return FALSE;
206 s = bfd_make_section_with_flags (abfd, ".gnu.version",
207 flags | SEC_READONLY);
208 if (s == NULL
209 || ! bfd_set_section_alignment (abfd, s, 1))
210 return FALSE;
212 s = bfd_make_section_with_flags (abfd, ".gnu.version_r",
213 flags | SEC_READONLY);
214 if (s == NULL
215 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
216 return FALSE;
218 s = bfd_make_section_with_flags (abfd, ".dynsym",
219 flags | SEC_READONLY);
220 if (s == NULL
221 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
222 return FALSE;
224 s = bfd_make_section_with_flags (abfd, ".dynstr",
225 flags | SEC_READONLY);
226 if (s == NULL)
227 return FALSE;
229 s = bfd_make_section_with_flags (abfd, ".dynamic", flags);
230 if (s == NULL
231 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
232 return FALSE;
234 /* The special symbol _DYNAMIC is always set to the start of the
235 .dynamic section. We could set _DYNAMIC in a linker script, but we
236 only want to define it if we are, in fact, creating a .dynamic
237 section. We don't want to define it if there is no .dynamic
238 section, since on some ELF platforms the start up code examines it
239 to decide how to initialize the process. */
240 if (!_bfd_elf_define_linkage_sym (abfd, info, s, "_DYNAMIC"))
241 return FALSE;
243 s = bfd_make_section_with_flags (abfd, ".hash",
244 flags | SEC_READONLY);
245 if (s == NULL
246 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
247 return FALSE;
248 elf_section_data (s)->this_hdr.sh_entsize = bed->s->sizeof_hash_entry;
250 /* Let the backend create the rest of the sections. This lets the
251 backend set the right flags. The backend will normally create
252 the .got and .plt sections. */
253 if (! (*bed->elf_backend_create_dynamic_sections) (abfd, info))
254 return FALSE;
256 elf_hash_table (info)->dynamic_sections_created = TRUE;
258 return TRUE;
261 /* Create dynamic sections when linking against a dynamic object. */
263 bfd_boolean
264 _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
266 flagword flags, pltflags;
267 struct elf_link_hash_entry *h;
268 asection *s;
269 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
271 /* We need to create .plt, .rel[a].plt, .got, .got.plt, .dynbss, and
272 .rel[a].bss sections. */
273 flags = bed->dynamic_sec_flags;
275 pltflags = flags;
276 if (bed->plt_not_loaded)
277 /* We do not clear SEC_ALLOC here because we still want the OS to
278 allocate space for the section; it's just that there's nothing
279 to read in from the object file. */
280 pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS);
281 else
282 pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD;
283 if (bed->plt_readonly)
284 pltflags |= SEC_READONLY;
286 s = bfd_make_section_with_flags (abfd, ".plt", pltflags);
287 if (s == NULL
288 || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment))
289 return FALSE;
291 /* Define the symbol _PROCEDURE_LINKAGE_TABLE_ at the start of the
292 .plt section. */
293 if (bed->want_plt_sym)
295 h = _bfd_elf_define_linkage_sym (abfd, info, s,
296 "_PROCEDURE_LINKAGE_TABLE_");
297 elf_hash_table (info)->hplt = h;
298 if (h == NULL)
299 return FALSE;
302 s = bfd_make_section_with_flags (abfd,
303 (bed->default_use_rela_p
304 ? ".rela.plt" : ".rel.plt"),
305 flags | SEC_READONLY);
306 if (s == NULL
307 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
308 return FALSE;
310 if (! _bfd_elf_create_got_section (abfd, info))
311 return FALSE;
313 if (bed->want_dynbss)
315 /* The .dynbss section is a place to put symbols which are defined
316 by dynamic objects, are referenced by regular objects, and are
317 not functions. We must allocate space for them in the process
318 image and use a R_*_COPY reloc to tell the dynamic linker to
319 initialize them at run time. The linker script puts the .dynbss
320 section into the .bss section of the final image. */
321 s = bfd_make_section_with_flags (abfd, ".dynbss",
322 (SEC_ALLOC
323 | SEC_LINKER_CREATED));
324 if (s == NULL)
325 return FALSE;
327 /* The .rel[a].bss section holds copy relocs. This section is not
328 normally needed. We need to create it here, though, so that the
329 linker will map it to an output section. We can't just create it
330 only if we need it, because we will not know whether we need it
331 until we have seen all the input files, and the first time the
332 main linker code calls BFD after examining all the input files
333 (size_dynamic_sections) the input sections have already been
334 mapped to the output sections. If the section turns out not to
335 be needed, we can discard it later. We will never need this
336 section when generating a shared object, since they do not use
337 copy relocs. */
338 if (! info->shared)
340 s = bfd_make_section_with_flags (abfd,
341 (bed->default_use_rela_p
342 ? ".rela.bss" : ".rel.bss"),
343 flags | SEC_READONLY);
344 if (s == NULL
345 || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
346 return FALSE;
350 return TRUE;
353 /* Record a new dynamic symbol. We record the dynamic symbols as we
354 read the input files, since we need to have a list of all of them
355 before we can determine the final sizes of the output sections.
356 Note that we may actually call this function even though we are not
357 going to output any dynamic symbols; in some cases we know that a
358 symbol should be in the dynamic symbol table, but only if there is
359 one. */
361 bfd_boolean
362 bfd_elf_link_record_dynamic_symbol (struct bfd_link_info *info,
363 struct elf_link_hash_entry *h)
365 if (h->dynindx == -1)
367 struct elf_strtab_hash *dynstr;
368 char *p;
369 const char *name;
370 bfd_size_type indx;
372 /* XXX: The ABI draft says the linker must turn hidden and
373 internal symbols into STB_LOCAL symbols when producing the
374 DSO. However, if ld.so honors st_other in the dynamic table,
375 this would not be necessary. */
376 switch (ELF_ST_VISIBILITY (h->other))
378 case STV_INTERNAL:
379 case STV_HIDDEN:
380 if (h->root.type != bfd_link_hash_undefined
381 && h->root.type != bfd_link_hash_undefweak)
383 h->forced_local = 1;
384 if (!elf_hash_table (info)->is_relocatable_executable)
385 return TRUE;
388 default:
389 break;
392 h->dynindx = elf_hash_table (info)->dynsymcount;
393 ++elf_hash_table (info)->dynsymcount;
395 dynstr = elf_hash_table (info)->dynstr;
396 if (dynstr == NULL)
398 /* Create a strtab to hold the dynamic symbol names. */
399 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
400 if (dynstr == NULL)
401 return FALSE;
404 /* We don't put any version information in the dynamic string
405 table. */
406 name = h->root.root.string;
407 p = strchr (name, ELF_VER_CHR);
408 if (p != NULL)
409 /* We know that the p points into writable memory. In fact,
410 there are only a few symbols that have read-only names, being
411 those like _GLOBAL_OFFSET_TABLE_ that are created specially
412 by the backends. Most symbols will have names pointing into
413 an ELF string table read from a file, or to objalloc memory. */
414 *p = 0;
416 indx = _bfd_elf_strtab_add (dynstr, name, p != NULL);
418 if (p != NULL)
419 *p = ELF_VER_CHR;
421 if (indx == (bfd_size_type) -1)
422 return FALSE;
423 h->dynstr_index = indx;
426 return TRUE;
429 /* Record an assignment to a symbol made by a linker script. We need
430 this in case some dynamic object refers to this symbol. */
432 bfd_boolean
433 bfd_elf_record_link_assignment (bfd *output_bfd,
434 struct bfd_link_info *info,
435 const char *name,
436 bfd_boolean provide,
437 bfd_boolean hidden)
439 struct elf_link_hash_entry *h;
440 struct elf_link_hash_table *htab;
442 if (!is_elf_hash_table (info->hash))
443 return TRUE;
445 htab = elf_hash_table (info);
446 h = elf_link_hash_lookup (htab, name, !provide, TRUE, FALSE);
447 if (h == NULL)
448 return provide;
450 /* Since we're defining the symbol, don't let it seem to have not
451 been defined. record_dynamic_symbol and size_dynamic_sections
452 may depend on this. */
453 if (h->root.type == bfd_link_hash_undefweak
454 || h->root.type == bfd_link_hash_undefined)
456 h->root.type = bfd_link_hash_new;
457 if (h->root.u.undef.next != NULL || htab->root.undefs_tail == &h->root)
458 bfd_link_repair_undef_list (&htab->root);
461 if (h->root.type == bfd_link_hash_new)
462 h->non_elf = 0;
464 /* If this symbol is being provided by the linker script, and it is
465 currently defined by a dynamic object, but not by a regular
466 object, then mark it as undefined so that the generic linker will
467 force the correct value. */
468 if (provide
469 && h->def_dynamic
470 && !h->def_regular)
471 h->root.type = bfd_link_hash_undefined;
473 /* If this symbol is not being provided by the linker script, and it is
474 currently defined by a dynamic object, but not by a regular object,
475 then clear out any version information because the symbol will not be
476 associated with the dynamic object any more. */
477 if (!provide
478 && h->def_dynamic
479 && !h->def_regular)
480 h->verinfo.verdef = NULL;
482 h->def_regular = 1;
484 if (provide && hidden)
486 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
488 h->other = (h->other & ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN;
489 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
492 /* STV_HIDDEN and STV_INTERNAL symbols must be STB_LOCAL in shared objects
493 and executables. */
494 if (!info->relocatable
495 && h->dynindx != -1
496 && (ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
497 || ELF_ST_VISIBILITY (h->other) == STV_INTERNAL))
498 h->forced_local = 1;
500 if ((h->def_dynamic
501 || h->ref_dynamic
502 || info->shared
503 || (info->executable && elf_hash_table (info)->is_relocatable_executable))
504 && h->dynindx == -1)
506 if (! bfd_elf_link_record_dynamic_symbol (info, h))
507 return FALSE;
509 /* If this is a weak defined symbol, and we know a corresponding
510 real symbol from the same dynamic object, make sure the real
511 symbol is also made into a dynamic symbol. */
512 if (h->u.weakdef != NULL
513 && h->u.weakdef->dynindx == -1)
515 if (! bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
516 return FALSE;
520 return TRUE;
523 /* Record a new local dynamic symbol. Returns 0 on failure, 1 on
524 success, and 2 on a failure caused by attempting to record a symbol
525 in a discarded section, eg. a discarded link-once section symbol. */
528 bfd_elf_link_record_local_dynamic_symbol (struct bfd_link_info *info,
529 bfd *input_bfd,
530 long input_indx)
532 bfd_size_type amt;
533 struct elf_link_local_dynamic_entry *entry;
534 struct elf_link_hash_table *eht;
535 struct elf_strtab_hash *dynstr;
536 unsigned long dynstr_index;
537 char *name;
538 Elf_External_Sym_Shndx eshndx;
539 char esym[sizeof (Elf64_External_Sym)];
541 if (! is_elf_hash_table (info->hash))
542 return 0;
544 /* See if the entry exists already. */
545 for (entry = elf_hash_table (info)->dynlocal; entry ; entry = entry->next)
546 if (entry->input_bfd == input_bfd && entry->input_indx == input_indx)
547 return 1;
549 amt = sizeof (*entry);
550 entry = bfd_alloc (input_bfd, amt);
551 if (entry == NULL)
552 return 0;
554 /* Go find the symbol, so that we can find it's name. */
555 if (!bfd_elf_get_elf_syms (input_bfd, &elf_tdata (input_bfd)->symtab_hdr,
556 1, input_indx, &entry->isym, esym, &eshndx))
558 bfd_release (input_bfd, entry);
559 return 0;
562 if (entry->isym.st_shndx != SHN_UNDEF
563 && (entry->isym.st_shndx < SHN_LORESERVE
564 || entry->isym.st_shndx > SHN_HIRESERVE))
566 asection *s;
568 s = bfd_section_from_elf_index (input_bfd, entry->isym.st_shndx);
569 if (s == NULL || bfd_is_abs_section (s->output_section))
571 /* We can still bfd_release here as nothing has done another
572 bfd_alloc. We can't do this later in this function. */
573 bfd_release (input_bfd, entry);
574 return 2;
578 name = (bfd_elf_string_from_elf_section
579 (input_bfd, elf_tdata (input_bfd)->symtab_hdr.sh_link,
580 entry->isym.st_name));
582 dynstr = elf_hash_table (info)->dynstr;
583 if (dynstr == NULL)
585 /* Create a strtab to hold the dynamic symbol names. */
586 elf_hash_table (info)->dynstr = dynstr = _bfd_elf_strtab_init ();
587 if (dynstr == NULL)
588 return 0;
591 dynstr_index = _bfd_elf_strtab_add (dynstr, name, FALSE);
592 if (dynstr_index == (unsigned long) -1)
593 return 0;
594 entry->isym.st_name = dynstr_index;
596 eht = elf_hash_table (info);
598 entry->next = eht->dynlocal;
599 eht->dynlocal = entry;
600 entry->input_bfd = input_bfd;
601 entry->input_indx = input_indx;
602 eht->dynsymcount++;
604 /* Whatever binding the symbol had before, it's now local. */
605 entry->isym.st_info
606 = ELF_ST_INFO (STB_LOCAL, ELF_ST_TYPE (entry->isym.st_info));
608 /* The dynindx will be set at the end of size_dynamic_sections. */
610 return 1;
613 /* Return the dynindex of a local dynamic symbol. */
615 long
616 _bfd_elf_link_lookup_local_dynindx (struct bfd_link_info *info,
617 bfd *input_bfd,
618 long input_indx)
620 struct elf_link_local_dynamic_entry *e;
622 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
623 if (e->input_bfd == input_bfd && e->input_indx == input_indx)
624 return e->dynindx;
625 return -1;
628 /* This function is used to renumber the dynamic symbols, if some of
629 them are removed because they are marked as local. This is called
630 via elf_link_hash_traverse. */
632 static bfd_boolean
633 elf_link_renumber_hash_table_dynsyms (struct elf_link_hash_entry *h,
634 void *data)
636 size_t *count = data;
638 if (h->root.type == bfd_link_hash_warning)
639 h = (struct elf_link_hash_entry *) h->root.u.i.link;
641 if (h->forced_local)
642 return TRUE;
644 if (h->dynindx != -1)
645 h->dynindx = ++(*count);
647 return TRUE;
651 /* Like elf_link_renumber_hash_table_dynsyms, but just number symbols with
652 STB_LOCAL binding. */
654 static bfd_boolean
655 elf_link_renumber_local_hash_table_dynsyms (struct elf_link_hash_entry *h,
656 void *data)
658 size_t *count = data;
660 if (h->root.type == bfd_link_hash_warning)
661 h = (struct elf_link_hash_entry *) h->root.u.i.link;
663 if (!h->forced_local)
664 return TRUE;
666 if (h->dynindx != -1)
667 h->dynindx = ++(*count);
669 return TRUE;
672 /* Return true if the dynamic symbol for a given section should be
673 omitted when creating a shared library. */
674 bfd_boolean
675 _bfd_elf_link_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED,
676 struct bfd_link_info *info,
677 asection *p)
679 switch (elf_section_data (p)->this_hdr.sh_type)
681 case SHT_PROGBITS:
682 case SHT_NOBITS:
683 /* If sh_type is yet undecided, assume it could be
684 SHT_PROGBITS/SHT_NOBITS. */
685 case SHT_NULL:
686 if (strcmp (p->name, ".got") == 0
687 || strcmp (p->name, ".got.plt") == 0
688 || strcmp (p->name, ".plt") == 0)
690 asection *ip;
691 bfd *dynobj = elf_hash_table (info)->dynobj;
693 if (dynobj != NULL
694 && (ip = bfd_get_section_by_name (dynobj, p->name)) != NULL
695 && (ip->flags & SEC_LINKER_CREATED)
696 && ip->output_section == p)
697 return TRUE;
699 return FALSE;
701 /* There shouldn't be section relative relocations
702 against any other section. */
703 default:
704 return TRUE;
708 /* Assign dynsym indices. In a shared library we generate a section
709 symbol for each output section, which come first. Next come symbols
710 which have been forced to local binding. Then all of the back-end
711 allocated local dynamic syms, followed by the rest of the global
712 symbols. */
714 static unsigned long
715 _bfd_elf_link_renumber_dynsyms (bfd *output_bfd,
716 struct bfd_link_info *info,
717 unsigned long *section_sym_count)
719 unsigned long dynsymcount = 0;
721 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
723 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
724 asection *p;
725 for (p = output_bfd->sections; p ; p = p->next)
726 if ((p->flags & SEC_EXCLUDE) == 0
727 && (p->flags & SEC_ALLOC) != 0
728 && !(*bed->elf_backend_omit_section_dynsym) (output_bfd, info, p))
729 elf_section_data (p)->dynindx = ++dynsymcount;
731 *section_sym_count = dynsymcount;
733 elf_link_hash_traverse (elf_hash_table (info),
734 elf_link_renumber_local_hash_table_dynsyms,
735 &dynsymcount);
737 if (elf_hash_table (info)->dynlocal)
739 struct elf_link_local_dynamic_entry *p;
740 for (p = elf_hash_table (info)->dynlocal; p ; p = p->next)
741 p->dynindx = ++dynsymcount;
744 elf_link_hash_traverse (elf_hash_table (info),
745 elf_link_renumber_hash_table_dynsyms,
746 &dynsymcount);
748 /* There is an unused NULL entry at the head of the table which
749 we must account for in our count. Unless there weren't any
750 symbols, which means we'll have no table at all. */
751 if (dynsymcount != 0)
752 ++dynsymcount;
754 elf_hash_table (info)->dynsymcount = dynsymcount;
755 return dynsymcount;
758 /* This function is called when we want to define a new symbol. It
759 handles the various cases which arise when we find a definition in
760 a dynamic object, or when there is already a definition in a
761 dynamic object. The new symbol is described by NAME, SYM, PSEC,
762 and PVALUE. We set SYM_HASH to the hash table entry. We set
763 OVERRIDE if the old symbol is overriding a new definition. We set
764 TYPE_CHANGE_OK if it is OK for the type to change. We set
765 SIZE_CHANGE_OK if it is OK for the size to change. By OK to
766 change, we mean that we shouldn't warn if the type or size does
767 change. We set POLD_ALIGNMENT if an old common symbol in a dynamic
768 object is overridden by a regular object. */
770 bfd_boolean
771 _bfd_elf_merge_symbol (bfd *abfd,
772 struct bfd_link_info *info,
773 const char *name,
774 Elf_Internal_Sym *sym,
775 asection **psec,
776 bfd_vma *pvalue,
777 unsigned int *pold_alignment,
778 struct elf_link_hash_entry **sym_hash,
779 bfd_boolean *skip,
780 bfd_boolean *override,
781 bfd_boolean *type_change_ok,
782 bfd_boolean *size_change_ok)
784 asection *sec, *oldsec;
785 struct elf_link_hash_entry *h;
786 struct elf_link_hash_entry *flip;
787 int bind;
788 bfd *oldbfd;
789 bfd_boolean newdyn, olddyn, olddef, newdef, newdyncommon, olddyncommon;
790 bfd_boolean newweak, oldweak;
791 const struct elf_backend_data *bed;
793 *skip = FALSE;
794 *override = FALSE;
796 sec = *psec;
797 bind = ELF_ST_BIND (sym->st_info);
799 if (! bfd_is_und_section (sec))
800 h = elf_link_hash_lookup (elf_hash_table (info), name, TRUE, FALSE, FALSE);
801 else
802 h = ((struct elf_link_hash_entry *)
803 bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, FALSE, FALSE));
804 if (h == NULL)
805 return FALSE;
806 *sym_hash = h;
808 /* This code is for coping with dynamic objects, and is only useful
809 if we are doing an ELF link. */
810 if (info->hash->creator != abfd->xvec)
811 return TRUE;
813 /* For merging, we only care about real symbols. */
815 while (h->root.type == bfd_link_hash_indirect
816 || h->root.type == bfd_link_hash_warning)
817 h = (struct elf_link_hash_entry *) h->root.u.i.link;
819 /* If we just created the symbol, mark it as being an ELF symbol.
820 Other than that, there is nothing to do--there is no merge issue
821 with a newly defined symbol--so we just return. */
823 if (h->root.type == bfd_link_hash_new)
825 h->non_elf = 0;
826 return TRUE;
829 /* OLDBFD and OLDSEC are a BFD and an ASECTION associated with the
830 existing symbol. */
832 switch (h->root.type)
834 default:
835 oldbfd = NULL;
836 oldsec = NULL;
837 break;
839 case bfd_link_hash_undefined:
840 case bfd_link_hash_undefweak:
841 oldbfd = h->root.u.undef.abfd;
842 oldsec = NULL;
843 break;
845 case bfd_link_hash_defined:
846 case bfd_link_hash_defweak:
847 oldbfd = h->root.u.def.section->owner;
848 oldsec = h->root.u.def.section;
849 break;
851 case bfd_link_hash_common:
852 oldbfd = h->root.u.c.p->section->owner;
853 oldsec = h->root.u.c.p->section;
854 break;
857 /* In cases involving weak versioned symbols, we may wind up trying
858 to merge a symbol with itself. Catch that here, to avoid the
859 confusion that results if we try to override a symbol with
860 itself. The additional tests catch cases like
861 _GLOBAL_OFFSET_TABLE_, which are regular symbols defined in a
862 dynamic object, which we do want to handle here. */
863 if (abfd == oldbfd
864 && ((abfd->flags & DYNAMIC) == 0
865 || !h->def_regular))
866 return TRUE;
868 /* NEWDYN and OLDDYN indicate whether the new or old symbol,
869 respectively, is from a dynamic object. */
871 newdyn = (abfd->flags & DYNAMIC) != 0;
873 olddyn = FALSE;
874 if (oldbfd != NULL)
875 olddyn = (oldbfd->flags & DYNAMIC) != 0;
876 else if (oldsec != NULL)
878 /* This handles the special SHN_MIPS_{TEXT,DATA} section
879 indices used by MIPS ELF. */
880 olddyn = (oldsec->symbol->flags & BSF_DYNAMIC) != 0;
883 /* NEWDEF and OLDDEF indicate whether the new or old symbol,
884 respectively, appear to be a definition rather than reference. */
886 newdef = !bfd_is_und_section (sec) && !bfd_is_com_section (sec);
888 olddef = (h->root.type != bfd_link_hash_undefined
889 && h->root.type != bfd_link_hash_undefweak
890 && h->root.type != bfd_link_hash_common);
892 /* When we try to create a default indirect symbol from the dynamic
893 definition with the default version, we skip it if its type and
894 the type of existing regular definition mismatch. We only do it
895 if the existing regular definition won't be dynamic. */
896 if (pold_alignment == NULL
897 && !info->shared
898 && !info->export_dynamic
899 && !h->ref_dynamic
900 && newdyn
901 && newdef
902 && !olddyn
903 && (olddef || h->root.type == bfd_link_hash_common)
904 && ELF_ST_TYPE (sym->st_info) != h->type
905 && ELF_ST_TYPE (sym->st_info) != STT_NOTYPE
906 && h->type != STT_NOTYPE)
908 *skip = TRUE;
909 return TRUE;
912 /* Check TLS symbol. We don't check undefined symbol introduced by
913 "ld -u". */
914 if ((ELF_ST_TYPE (sym->st_info) == STT_TLS || h->type == STT_TLS)
915 && ELF_ST_TYPE (sym->st_info) != h->type
916 && oldbfd != NULL)
918 bfd *ntbfd, *tbfd;
919 bfd_boolean ntdef, tdef;
920 asection *ntsec, *tsec;
922 if (h->type == STT_TLS)
924 ntbfd = abfd;
925 ntsec = sec;
926 ntdef = newdef;
927 tbfd = oldbfd;
928 tsec = oldsec;
929 tdef = olddef;
931 else
933 ntbfd = oldbfd;
934 ntsec = oldsec;
935 ntdef = olddef;
936 tbfd = abfd;
937 tsec = sec;
938 tdef = newdef;
941 if (tdef && ntdef)
942 (*_bfd_error_handler)
943 (_("%s: TLS definition in %B section %A mismatches non-TLS definition in %B section %A"),
944 tbfd, tsec, ntbfd, ntsec, h->root.root.string);
945 else if (!tdef && !ntdef)
946 (*_bfd_error_handler)
947 (_("%s: TLS reference in %B mismatches non-TLS reference in %B"),
948 tbfd, ntbfd, h->root.root.string);
949 else if (tdef)
950 (*_bfd_error_handler)
951 (_("%s: TLS definition in %B section %A mismatches non-TLS reference in %B"),
952 tbfd, tsec, ntbfd, h->root.root.string);
953 else
954 (*_bfd_error_handler)
955 (_("%s: TLS reference in %B mismatches non-TLS definition in %B section %A"),
956 tbfd, ntbfd, ntsec, h->root.root.string);
958 bfd_set_error (bfd_error_bad_value);
959 return FALSE;
962 /* We need to remember if a symbol has a definition in a dynamic
963 object or is weak in all dynamic objects. Internal and hidden
964 visibility will make it unavailable to dynamic objects. */
965 if (newdyn && !h->dynamic_def)
967 if (!bfd_is_und_section (sec))
968 h->dynamic_def = 1;
969 else
971 /* Check if this symbol is weak in all dynamic objects. If it
972 is the first time we see it in a dynamic object, we mark
973 if it is weak. Otherwise, we clear it. */
974 if (!h->ref_dynamic)
976 if (bind == STB_WEAK)
977 h->dynamic_weak = 1;
979 else if (bind != STB_WEAK)
980 h->dynamic_weak = 0;
984 /* If the old symbol has non-default visibility, we ignore the new
985 definition from a dynamic object. */
986 if (newdyn
987 && ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
988 && !bfd_is_und_section (sec))
990 *skip = TRUE;
991 /* Make sure this symbol is dynamic. */
992 h->ref_dynamic = 1;
993 /* A protected symbol has external availability. Make sure it is
994 recorded as dynamic.
996 FIXME: Should we check type and size for protected symbol? */
997 if (ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
998 return bfd_elf_link_record_dynamic_symbol (info, h);
999 else
1000 return TRUE;
1002 else if (!newdyn
1003 && ELF_ST_VISIBILITY (sym->st_other) != STV_DEFAULT
1004 && h->def_dynamic)
1006 /* If the new symbol with non-default visibility comes from a
1007 relocatable file and the old definition comes from a dynamic
1008 object, we remove the old definition. */
1009 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1010 h = *sym_hash;
1012 if ((h->root.u.undef.next || info->hash->undefs_tail == &h->root)
1013 && bfd_is_und_section (sec))
1015 /* If the new symbol is undefined and the old symbol was
1016 also undefined before, we need to make sure
1017 _bfd_generic_link_add_one_symbol doesn't mess
1018 up the linker hash table undefs list. Since the old
1019 definition came from a dynamic object, it is still on the
1020 undefs list. */
1021 h->root.type = bfd_link_hash_undefined;
1022 h->root.u.undef.abfd = abfd;
1024 else
1026 h->root.type = bfd_link_hash_new;
1027 h->root.u.undef.abfd = NULL;
1030 if (h->def_dynamic)
1032 h->def_dynamic = 0;
1033 h->ref_dynamic = 1;
1034 h->dynamic_def = 1;
1036 /* FIXME: Should we check type and size for protected symbol? */
1037 h->size = 0;
1038 h->type = 0;
1039 return TRUE;
1042 /* Differentiate strong and weak symbols. */
1043 newweak = bind == STB_WEAK;
1044 oldweak = (h->root.type == bfd_link_hash_defweak
1045 || h->root.type == bfd_link_hash_undefweak);
1047 /* If a new weak symbol definition comes from a regular file and the
1048 old symbol comes from a dynamic library, we treat the new one as
1049 strong. Similarly, an old weak symbol definition from a regular
1050 file is treated as strong when the new symbol comes from a dynamic
1051 library. Further, an old weak symbol from a dynamic library is
1052 treated as strong if the new symbol is from a dynamic library.
1053 This reflects the way glibc's ld.so works.
1055 Do this before setting *type_change_ok or *size_change_ok so that
1056 we warn properly when dynamic library symbols are overridden. */
1058 if (newdef && !newdyn && olddyn)
1059 newweak = FALSE;
1060 if (olddef && newdyn)
1061 oldweak = FALSE;
1063 /* It's OK to change the type if either the existing symbol or the
1064 new symbol is weak. A type change is also OK if the old symbol
1065 is undefined and the new symbol is defined. */
1067 if (oldweak
1068 || newweak
1069 || (newdef
1070 && h->root.type == bfd_link_hash_undefined))
1071 *type_change_ok = TRUE;
1073 /* It's OK to change the size if either the existing symbol or the
1074 new symbol is weak, or if the old symbol is undefined. */
1076 if (*type_change_ok
1077 || h->root.type == bfd_link_hash_undefined)
1078 *size_change_ok = TRUE;
1080 /* NEWDYNCOMMON and OLDDYNCOMMON indicate whether the new or old
1081 symbol, respectively, appears to be a common symbol in a dynamic
1082 object. If a symbol appears in an uninitialized section, and is
1083 not weak, and is not a function, then it may be a common symbol
1084 which was resolved when the dynamic object was created. We want
1085 to treat such symbols specially, because they raise special
1086 considerations when setting the symbol size: if the symbol
1087 appears as a common symbol in a regular object, and the size in
1088 the regular object is larger, we must make sure that we use the
1089 larger size. This problematic case can always be avoided in C,
1090 but it must be handled correctly when using Fortran shared
1091 libraries.
1093 Note that if NEWDYNCOMMON is set, NEWDEF will be set, and
1094 likewise for OLDDYNCOMMON and OLDDEF.
1096 Note that this test is just a heuristic, and that it is quite
1097 possible to have an uninitialized symbol in a shared object which
1098 is really a definition, rather than a common symbol. This could
1099 lead to some minor confusion when the symbol really is a common
1100 symbol in some regular object. However, I think it will be
1101 harmless. */
1103 if (newdyn
1104 && newdef
1105 && !newweak
1106 && (sec->flags & SEC_ALLOC) != 0
1107 && (sec->flags & SEC_LOAD) == 0
1108 && sym->st_size > 0
1109 && ELF_ST_TYPE (sym->st_info) != STT_FUNC)
1110 newdyncommon = TRUE;
1111 else
1112 newdyncommon = FALSE;
1114 if (olddyn
1115 && olddef
1116 && h->root.type == bfd_link_hash_defined
1117 && h->def_dynamic
1118 && (h->root.u.def.section->flags & SEC_ALLOC) != 0
1119 && (h->root.u.def.section->flags & SEC_LOAD) == 0
1120 && h->size > 0
1121 && h->type != STT_FUNC)
1122 olddyncommon = TRUE;
1123 else
1124 olddyncommon = FALSE;
1126 /* We now know everything about the old and new symbols. We ask the
1127 backend to check if we can merge them. */
1128 bed = get_elf_backend_data (abfd);
1129 if (bed->merge_symbol
1130 && !bed->merge_symbol (info, sym_hash, h, sym, psec, pvalue,
1131 pold_alignment, skip, override,
1132 type_change_ok, size_change_ok,
1133 &newdyn, &newdef, &newdyncommon, &newweak,
1134 abfd, &sec,
1135 &olddyn, &olddef, &olddyncommon, &oldweak,
1136 oldbfd, &oldsec))
1137 return FALSE;
1139 /* If both the old and the new symbols look like common symbols in a
1140 dynamic object, set the size of the symbol to the larger of the
1141 two. */
1143 if (olddyncommon
1144 && newdyncommon
1145 && sym->st_size != h->size)
1147 /* Since we think we have two common symbols, issue a multiple
1148 common warning if desired. Note that we only warn if the
1149 size is different. If the size is the same, we simply let
1150 the old symbol override the new one as normally happens with
1151 symbols defined in dynamic objects. */
1153 if (! ((*info->callbacks->multiple_common)
1154 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1155 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1156 return FALSE;
1158 if (sym->st_size > h->size)
1159 h->size = sym->st_size;
1161 *size_change_ok = TRUE;
1164 /* If we are looking at a dynamic object, and we have found a
1165 definition, we need to see if the symbol was already defined by
1166 some other object. If so, we want to use the existing
1167 definition, and we do not want to report a multiple symbol
1168 definition error; we do this by clobbering *PSEC to be
1169 bfd_und_section_ptr.
1171 We treat a common symbol as a definition if the symbol in the
1172 shared library is a function, since common symbols always
1173 represent variables; this can cause confusion in principle, but
1174 any such confusion would seem to indicate an erroneous program or
1175 shared library. We also permit a common symbol in a regular
1176 object to override a weak symbol in a shared object. */
1178 if (newdyn
1179 && newdef
1180 && (olddef
1181 || (h->root.type == bfd_link_hash_common
1182 && (newweak
1183 || ELF_ST_TYPE (sym->st_info) == STT_FUNC))))
1185 *override = TRUE;
1186 newdef = FALSE;
1187 newdyncommon = FALSE;
1189 *psec = sec = bfd_und_section_ptr;
1190 *size_change_ok = TRUE;
1192 /* If we get here when the old symbol is a common symbol, then
1193 we are explicitly letting it override a weak symbol or
1194 function in a dynamic object, and we don't want to warn about
1195 a type change. If the old symbol is a defined symbol, a type
1196 change warning may still be appropriate. */
1198 if (h->root.type == bfd_link_hash_common)
1199 *type_change_ok = TRUE;
1202 /* Handle the special case of an old common symbol merging with a
1203 new symbol which looks like a common symbol in a shared object.
1204 We change *PSEC and *PVALUE to make the new symbol look like a
1205 common symbol, and let _bfd_generic_link_add_one_symbol do the
1206 right thing. */
1208 if (newdyncommon
1209 && h->root.type == bfd_link_hash_common)
1211 *override = TRUE;
1212 newdef = FALSE;
1213 newdyncommon = FALSE;
1214 *pvalue = sym->st_size;
1215 *psec = sec = bed->common_section (oldsec);
1216 *size_change_ok = TRUE;
1219 /* Skip weak definitions of symbols that are already defined. */
1220 if (newdef && olddef && newweak)
1221 *skip = TRUE;
1223 /* If the old symbol is from a dynamic object, and the new symbol is
1224 a definition which is not from a dynamic object, then the new
1225 symbol overrides the old symbol. Symbols from regular files
1226 always take precedence over symbols from dynamic objects, even if
1227 they are defined after the dynamic object in the link.
1229 As above, we again permit a common symbol in a regular object to
1230 override a definition in a shared object if the shared object
1231 symbol is a function or is weak. */
1233 flip = NULL;
1234 if (!newdyn
1235 && (newdef
1236 || (bfd_is_com_section (sec)
1237 && (oldweak
1238 || h->type == STT_FUNC)))
1239 && olddyn
1240 && olddef
1241 && h->def_dynamic)
1243 /* Change the hash table entry to undefined, and let
1244 _bfd_generic_link_add_one_symbol do the right thing with the
1245 new definition. */
1247 h->root.type = bfd_link_hash_undefined;
1248 h->root.u.undef.abfd = h->root.u.def.section->owner;
1249 *size_change_ok = TRUE;
1251 olddef = FALSE;
1252 olddyncommon = FALSE;
1254 /* We again permit a type change when a common symbol may be
1255 overriding a function. */
1257 if (bfd_is_com_section (sec))
1258 *type_change_ok = TRUE;
1260 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1261 flip = *sym_hash;
1262 else
1263 /* This union may have been set to be non-NULL when this symbol
1264 was seen in a dynamic object. We must force the union to be
1265 NULL, so that it is correct for a regular symbol. */
1266 h->verinfo.vertree = NULL;
1269 /* Handle the special case of a new common symbol merging with an
1270 old symbol that looks like it might be a common symbol defined in
1271 a shared object. Note that we have already handled the case in
1272 which a new common symbol should simply override the definition
1273 in the shared library. */
1275 if (! newdyn
1276 && bfd_is_com_section (sec)
1277 && olddyncommon)
1279 /* It would be best if we could set the hash table entry to a
1280 common symbol, but we don't know what to use for the section
1281 or the alignment. */
1282 if (! ((*info->callbacks->multiple_common)
1283 (info, h->root.root.string, oldbfd, bfd_link_hash_common,
1284 h->size, abfd, bfd_link_hash_common, sym->st_size)))
1285 return FALSE;
1287 /* If the presumed common symbol in the dynamic object is
1288 larger, pretend that the new symbol has its size. */
1290 if (h->size > *pvalue)
1291 *pvalue = h->size;
1293 /* We need to remember the alignment required by the symbol
1294 in the dynamic object. */
1295 BFD_ASSERT (pold_alignment);
1296 *pold_alignment = h->root.u.def.section->alignment_power;
1298 olddef = FALSE;
1299 olddyncommon = FALSE;
1301 h->root.type = bfd_link_hash_undefined;
1302 h->root.u.undef.abfd = h->root.u.def.section->owner;
1304 *size_change_ok = TRUE;
1305 *type_change_ok = TRUE;
1307 if ((*sym_hash)->root.type == bfd_link_hash_indirect)
1308 flip = *sym_hash;
1309 else
1310 h->verinfo.vertree = NULL;
1313 if (flip != NULL)
1315 /* Handle the case where we had a versioned symbol in a dynamic
1316 library and now find a definition in a normal object. In this
1317 case, we make the versioned symbol point to the normal one. */
1318 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
1319 flip->root.type = h->root.type;
1320 h->root.type = bfd_link_hash_indirect;
1321 h->root.u.i.link = (struct bfd_link_hash_entry *) flip;
1322 (*bed->elf_backend_copy_indirect_symbol) (info, flip, h);
1323 flip->root.u.undef.abfd = h->root.u.undef.abfd;
1324 if (h->def_dynamic)
1326 h->def_dynamic = 0;
1327 flip->ref_dynamic = 1;
1331 return TRUE;
1334 /* This function is called to create an indirect symbol from the
1335 default for the symbol with the default version if needed. The
1336 symbol is described by H, NAME, SYM, PSEC, VALUE, and OVERRIDE. We
1337 set DYNSYM if the new indirect symbol is dynamic. */
1339 bfd_boolean
1340 _bfd_elf_add_default_symbol (bfd *abfd,
1341 struct bfd_link_info *info,
1342 struct elf_link_hash_entry *h,
1343 const char *name,
1344 Elf_Internal_Sym *sym,
1345 asection **psec,
1346 bfd_vma *value,
1347 bfd_boolean *dynsym,
1348 bfd_boolean override)
1350 bfd_boolean type_change_ok;
1351 bfd_boolean size_change_ok;
1352 bfd_boolean skip;
1353 char *shortname;
1354 struct elf_link_hash_entry *hi;
1355 struct bfd_link_hash_entry *bh;
1356 const struct elf_backend_data *bed;
1357 bfd_boolean collect;
1358 bfd_boolean dynamic;
1359 char *p;
1360 size_t len, shortlen;
1361 asection *sec;
1363 /* If this symbol has a version, and it is the default version, we
1364 create an indirect symbol from the default name to the fully
1365 decorated name. This will cause external references which do not
1366 specify a version to be bound to this version of the symbol. */
1367 p = strchr (name, ELF_VER_CHR);
1368 if (p == NULL || p[1] != ELF_VER_CHR)
1369 return TRUE;
1371 if (override)
1373 /* We are overridden by an old definition. We need to check if we
1374 need to create the indirect symbol from the default name. */
1375 hi = elf_link_hash_lookup (elf_hash_table (info), name, TRUE,
1376 FALSE, FALSE);
1377 BFD_ASSERT (hi != NULL);
1378 if (hi == h)
1379 return TRUE;
1380 while (hi->root.type == bfd_link_hash_indirect
1381 || hi->root.type == bfd_link_hash_warning)
1383 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1384 if (hi == h)
1385 return TRUE;
1389 bed = get_elf_backend_data (abfd);
1390 collect = bed->collect;
1391 dynamic = (abfd->flags & DYNAMIC) != 0;
1393 shortlen = p - name;
1394 shortname = bfd_hash_allocate (&info->hash->table, shortlen + 1);
1395 if (shortname == NULL)
1396 return FALSE;
1397 memcpy (shortname, name, shortlen);
1398 shortname[shortlen] = '\0';
1400 /* We are going to create a new symbol. Merge it with any existing
1401 symbol with this name. For the purposes of the merge, act as
1402 though we were defining the symbol we just defined, although we
1403 actually going to define an indirect symbol. */
1404 type_change_ok = FALSE;
1405 size_change_ok = FALSE;
1406 sec = *psec;
1407 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1408 NULL, &hi, &skip, &override,
1409 &type_change_ok, &size_change_ok))
1410 return FALSE;
1412 if (skip)
1413 goto nondefault;
1415 if (! override)
1417 bh = &hi->root;
1418 if (! (_bfd_generic_link_add_one_symbol
1419 (info, abfd, shortname, BSF_INDIRECT, bfd_ind_section_ptr,
1420 0, name, FALSE, collect, &bh)))
1421 return FALSE;
1422 hi = (struct elf_link_hash_entry *) bh;
1424 else
1426 /* In this case the symbol named SHORTNAME is overriding the
1427 indirect symbol we want to add. We were planning on making
1428 SHORTNAME an indirect symbol referring to NAME. SHORTNAME
1429 is the name without a version. NAME is the fully versioned
1430 name, and it is the default version.
1432 Overriding means that we already saw a definition for the
1433 symbol SHORTNAME in a regular object, and it is overriding
1434 the symbol defined in the dynamic object.
1436 When this happens, we actually want to change NAME, the
1437 symbol we just added, to refer to SHORTNAME. This will cause
1438 references to NAME in the shared object to become references
1439 to SHORTNAME in the regular object. This is what we expect
1440 when we override a function in a shared object: that the
1441 references in the shared object will be mapped to the
1442 definition in the regular object. */
1444 while (hi->root.type == bfd_link_hash_indirect
1445 || hi->root.type == bfd_link_hash_warning)
1446 hi = (struct elf_link_hash_entry *) hi->root.u.i.link;
1448 h->root.type = bfd_link_hash_indirect;
1449 h->root.u.i.link = (struct bfd_link_hash_entry *) hi;
1450 if (h->def_dynamic)
1452 h->def_dynamic = 0;
1453 hi->ref_dynamic = 1;
1454 if (hi->ref_regular
1455 || hi->def_regular)
1457 if (! bfd_elf_link_record_dynamic_symbol (info, hi))
1458 return FALSE;
1462 /* Now set HI to H, so that the following code will set the
1463 other fields correctly. */
1464 hi = h;
1467 /* If there is a duplicate definition somewhere, then HI may not
1468 point to an indirect symbol. We will have reported an error to
1469 the user in that case. */
1471 if (hi->root.type == bfd_link_hash_indirect)
1473 struct elf_link_hash_entry *ht;
1475 ht = (struct elf_link_hash_entry *) hi->root.u.i.link;
1476 (*bed->elf_backend_copy_indirect_symbol) (info, ht, hi);
1478 /* See if the new flags lead us to realize that the symbol must
1479 be dynamic. */
1480 if (! *dynsym)
1482 if (! dynamic)
1484 if (info->shared
1485 || hi->ref_dynamic)
1486 *dynsym = TRUE;
1488 else
1490 if (hi->ref_regular)
1491 *dynsym = TRUE;
1496 /* We also need to define an indirection from the nondefault version
1497 of the symbol. */
1499 nondefault:
1500 len = strlen (name);
1501 shortname = bfd_hash_allocate (&info->hash->table, len);
1502 if (shortname == NULL)
1503 return FALSE;
1504 memcpy (shortname, name, shortlen);
1505 memcpy (shortname + shortlen, p + 1, len - shortlen);
1507 /* Once again, merge with any existing symbol. */
1508 type_change_ok = FALSE;
1509 size_change_ok = FALSE;
1510 sec = *psec;
1511 if (!_bfd_elf_merge_symbol (abfd, info, shortname, sym, &sec, value,
1512 NULL, &hi, &skip, &override,
1513 &type_change_ok, &size_change_ok))
1514 return FALSE;
1516 if (skip)
1517 return TRUE;
1519 if (override)
1521 /* Here SHORTNAME is a versioned name, so we don't expect to see
1522 the type of override we do in the case above unless it is
1523 overridden by a versioned definition. */
1524 if (hi->root.type != bfd_link_hash_defined
1525 && hi->root.type != bfd_link_hash_defweak)
1526 (*_bfd_error_handler)
1527 (_("%B: unexpected redefinition of indirect versioned symbol `%s'"),
1528 abfd, shortname);
1530 else
1532 bh = &hi->root;
1533 if (! (_bfd_generic_link_add_one_symbol
1534 (info, abfd, shortname, BSF_INDIRECT,
1535 bfd_ind_section_ptr, 0, name, FALSE, collect, &bh)))
1536 return FALSE;
1537 hi = (struct elf_link_hash_entry *) bh;
1539 /* If there is a duplicate definition somewhere, then HI may not
1540 point to an indirect symbol. We will have reported an error
1541 to the user in that case. */
1543 if (hi->root.type == bfd_link_hash_indirect)
1545 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
1547 /* See if the new flags lead us to realize that the symbol
1548 must be dynamic. */
1549 if (! *dynsym)
1551 if (! dynamic)
1553 if (info->shared
1554 || hi->ref_dynamic)
1555 *dynsym = TRUE;
1557 else
1559 if (hi->ref_regular)
1560 *dynsym = TRUE;
1566 return TRUE;
1569 /* This routine is used to export all defined symbols into the dynamic
1570 symbol table. It is called via elf_link_hash_traverse. */
1572 bfd_boolean
1573 _bfd_elf_export_symbol (struct elf_link_hash_entry *h, void *data)
1575 struct elf_info_failed *eif = data;
1577 /* Ignore indirect symbols. These are added by the versioning code. */
1578 if (h->root.type == bfd_link_hash_indirect)
1579 return TRUE;
1581 if (h->root.type == bfd_link_hash_warning)
1582 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1584 if (h->dynindx == -1
1585 && (h->def_regular
1586 || h->ref_regular))
1588 struct bfd_elf_version_tree *t;
1589 struct bfd_elf_version_expr *d;
1591 for (t = eif->verdefs; t != NULL; t = t->next)
1593 if (t->globals.list != NULL)
1595 d = (*t->match) (&t->globals, NULL, h->root.root.string);
1596 if (d != NULL)
1597 goto doit;
1600 if (t->locals.list != NULL)
1602 d = (*t->match) (&t->locals, NULL, h->root.root.string);
1603 if (d != NULL)
1604 return TRUE;
1608 if (!eif->verdefs)
1610 doit:
1611 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
1613 eif->failed = TRUE;
1614 return FALSE;
1619 return TRUE;
1622 /* Look through the symbols which are defined in other shared
1623 libraries and referenced here. Update the list of version
1624 dependencies. This will be put into the .gnu.version_r section.
1625 This function is called via elf_link_hash_traverse. */
1627 bfd_boolean
1628 _bfd_elf_link_find_version_dependencies (struct elf_link_hash_entry *h,
1629 void *data)
1631 struct elf_find_verdep_info *rinfo = data;
1632 Elf_Internal_Verneed *t;
1633 Elf_Internal_Vernaux *a;
1634 bfd_size_type amt;
1636 if (h->root.type == bfd_link_hash_warning)
1637 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1639 /* We only care about symbols defined in shared objects with version
1640 information. */
1641 if (!h->def_dynamic
1642 || h->def_regular
1643 || h->dynindx == -1
1644 || h->verinfo.verdef == NULL)
1645 return TRUE;
1647 /* See if we already know about this version. */
1648 for (t = elf_tdata (rinfo->output_bfd)->verref; t != NULL; t = t->vn_nextref)
1650 if (t->vn_bfd != h->verinfo.verdef->vd_bfd)
1651 continue;
1653 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
1654 if (a->vna_nodename == h->verinfo.verdef->vd_nodename)
1655 return TRUE;
1657 break;
1660 /* This is a new version. Add it to tree we are building. */
1662 if (t == NULL)
1664 amt = sizeof *t;
1665 t = bfd_zalloc (rinfo->output_bfd, amt);
1666 if (t == NULL)
1668 rinfo->failed = TRUE;
1669 return FALSE;
1672 t->vn_bfd = h->verinfo.verdef->vd_bfd;
1673 t->vn_nextref = elf_tdata (rinfo->output_bfd)->verref;
1674 elf_tdata (rinfo->output_bfd)->verref = t;
1677 amt = sizeof *a;
1678 a = bfd_zalloc (rinfo->output_bfd, amt);
1680 /* Note that we are copying a string pointer here, and testing it
1681 above. If bfd_elf_string_from_elf_section is ever changed to
1682 discard the string data when low in memory, this will have to be
1683 fixed. */
1684 a->vna_nodename = h->verinfo.verdef->vd_nodename;
1686 a->vna_flags = h->verinfo.verdef->vd_flags;
1687 a->vna_nextptr = t->vn_auxptr;
1689 h->verinfo.verdef->vd_exp_refno = rinfo->vers;
1690 ++rinfo->vers;
1692 a->vna_other = h->verinfo.verdef->vd_exp_refno + 1;
1694 t->vn_auxptr = a;
1696 return TRUE;
1699 /* Figure out appropriate versions for all the symbols. We may not
1700 have the version number script until we have read all of the input
1701 files, so until that point we don't know which symbols should be
1702 local. This function is called via elf_link_hash_traverse. */
1704 bfd_boolean
1705 _bfd_elf_link_assign_sym_version (struct elf_link_hash_entry *h, void *data)
1707 struct elf_assign_sym_version_info *sinfo;
1708 struct bfd_link_info *info;
1709 const struct elf_backend_data *bed;
1710 struct elf_info_failed eif;
1711 char *p;
1712 bfd_size_type amt;
1714 sinfo = data;
1715 info = sinfo->info;
1717 if (h->root.type == bfd_link_hash_warning)
1718 h = (struct elf_link_hash_entry *) h->root.u.i.link;
1720 /* Fix the symbol flags. */
1721 eif.failed = FALSE;
1722 eif.info = info;
1723 if (! _bfd_elf_fix_symbol_flags (h, &eif))
1725 if (eif.failed)
1726 sinfo->failed = TRUE;
1727 return FALSE;
1730 /* We only need version numbers for symbols defined in regular
1731 objects. */
1732 if (!h->def_regular)
1733 return TRUE;
1735 bed = get_elf_backend_data (sinfo->output_bfd);
1736 p = strchr (h->root.root.string, ELF_VER_CHR);
1737 if (p != NULL && h->verinfo.vertree == NULL)
1739 struct bfd_elf_version_tree *t;
1740 bfd_boolean hidden;
1742 hidden = TRUE;
1744 /* There are two consecutive ELF_VER_CHR characters if this is
1745 not a hidden symbol. */
1746 ++p;
1747 if (*p == ELF_VER_CHR)
1749 hidden = FALSE;
1750 ++p;
1753 /* If there is no version string, we can just return out. */
1754 if (*p == '\0')
1756 if (hidden)
1757 h->hidden = 1;
1758 return TRUE;
1761 /* Look for the version. If we find it, it is no longer weak. */
1762 for (t = sinfo->verdefs; t != NULL; t = t->next)
1764 if (strcmp (t->name, p) == 0)
1766 size_t len;
1767 char *alc;
1768 struct bfd_elf_version_expr *d;
1770 len = p - h->root.root.string;
1771 alc = bfd_malloc (len);
1772 if (alc == NULL)
1773 return FALSE;
1774 memcpy (alc, h->root.root.string, len - 1);
1775 alc[len - 1] = '\0';
1776 if (alc[len - 2] == ELF_VER_CHR)
1777 alc[len - 2] = '\0';
1779 h->verinfo.vertree = t;
1780 t->used = TRUE;
1781 d = NULL;
1783 if (t->globals.list != NULL)
1784 d = (*t->match) (&t->globals, NULL, alc);
1786 /* See if there is anything to force this symbol to
1787 local scope. */
1788 if (d == NULL && t->locals.list != NULL)
1790 d = (*t->match) (&t->locals, NULL, alc);
1791 if (d != NULL
1792 && h->dynindx != -1
1793 && ! info->export_dynamic)
1794 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1797 free (alc);
1798 break;
1802 /* If we are building an application, we need to create a
1803 version node for this version. */
1804 if (t == NULL && info->executable)
1806 struct bfd_elf_version_tree **pp;
1807 int version_index;
1809 /* If we aren't going to export this symbol, we don't need
1810 to worry about it. */
1811 if (h->dynindx == -1)
1812 return TRUE;
1814 amt = sizeof *t;
1815 t = bfd_zalloc (sinfo->output_bfd, amt);
1816 if (t == NULL)
1818 sinfo->failed = TRUE;
1819 return FALSE;
1822 t->name = p;
1823 t->name_indx = (unsigned int) -1;
1824 t->used = TRUE;
1826 version_index = 1;
1827 /* Don't count anonymous version tag. */
1828 if (sinfo->verdefs != NULL && sinfo->verdefs->vernum == 0)
1829 version_index = 0;
1830 for (pp = &sinfo->verdefs; *pp != NULL; pp = &(*pp)->next)
1831 ++version_index;
1832 t->vernum = version_index;
1834 *pp = t;
1836 h->verinfo.vertree = t;
1838 else if (t == NULL)
1840 /* We could not find the version for a symbol when
1841 generating a shared archive. Return an error. */
1842 (*_bfd_error_handler)
1843 (_("%B: undefined versioned symbol name %s"),
1844 sinfo->output_bfd, h->root.root.string);
1845 bfd_set_error (bfd_error_bad_value);
1846 sinfo->failed = TRUE;
1847 return FALSE;
1850 if (hidden)
1851 h->hidden = 1;
1854 /* If we don't have a version for this symbol, see if we can find
1855 something. */
1856 if (h->verinfo.vertree == NULL && sinfo->verdefs != NULL)
1858 struct bfd_elf_version_tree *t;
1859 struct bfd_elf_version_tree *local_ver;
1860 struct bfd_elf_version_expr *d;
1862 /* See if can find what version this symbol is in. If the
1863 symbol is supposed to be local, then don't actually register
1864 it. */
1865 local_ver = NULL;
1866 for (t = sinfo->verdefs; t != NULL; t = t->next)
1868 if (t->globals.list != NULL)
1870 bfd_boolean matched;
1872 matched = FALSE;
1873 d = NULL;
1874 while ((d = (*t->match) (&t->globals, d,
1875 h->root.root.string)) != NULL)
1876 if (d->symver)
1877 matched = TRUE;
1878 else
1880 /* There is a version without definition. Make
1881 the symbol the default definition for this
1882 version. */
1883 h->verinfo.vertree = t;
1884 local_ver = NULL;
1885 d->script = 1;
1886 break;
1888 if (d != NULL)
1889 break;
1890 else if (matched)
1891 /* There is no undefined version for this symbol. Hide the
1892 default one. */
1893 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1896 if (t->locals.list != NULL)
1898 d = NULL;
1899 while ((d = (*t->match) (&t->locals, d,
1900 h->root.root.string)) != NULL)
1902 local_ver = t;
1903 /* If the match is "*", keep looking for a more
1904 explicit, perhaps even global, match.
1905 XXX: Shouldn't this be !d->wildcard instead? */
1906 if (d->pattern[0] != '*' || d->pattern[1] != '\0')
1907 break;
1910 if (d != NULL)
1911 break;
1915 if (local_ver != NULL)
1917 h->verinfo.vertree = local_ver;
1918 if (h->dynindx != -1
1919 && ! info->export_dynamic)
1921 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
1926 return TRUE;
1929 /* Read and swap the relocs from the section indicated by SHDR. This
1930 may be either a REL or a RELA section. The relocations are
1931 translated into RELA relocations and stored in INTERNAL_RELOCS,
1932 which should have already been allocated to contain enough space.
1933 The EXTERNAL_RELOCS are a buffer where the external form of the
1934 relocations should be stored.
1936 Returns FALSE if something goes wrong. */
1938 static bfd_boolean
1939 elf_link_read_relocs_from_section (bfd *abfd,
1940 asection *sec,
1941 Elf_Internal_Shdr *shdr,
1942 void *external_relocs,
1943 Elf_Internal_Rela *internal_relocs)
1945 const struct elf_backend_data *bed;
1946 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
1947 const bfd_byte *erela;
1948 const bfd_byte *erelaend;
1949 Elf_Internal_Rela *irela;
1950 Elf_Internal_Shdr *symtab_hdr;
1951 size_t nsyms;
1953 /* Position ourselves at the start of the section. */
1954 if (bfd_seek (abfd, shdr->sh_offset, SEEK_SET) != 0)
1955 return FALSE;
1957 /* Read the relocations. */
1958 if (bfd_bread (external_relocs, shdr->sh_size, abfd) != shdr->sh_size)
1959 return FALSE;
1961 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
1962 nsyms = symtab_hdr->sh_size / symtab_hdr->sh_entsize;
1964 bed = get_elf_backend_data (abfd);
1966 /* Convert the external relocations to the internal format. */
1967 if (shdr->sh_entsize == bed->s->sizeof_rel)
1968 swap_in = bed->s->swap_reloc_in;
1969 else if (shdr->sh_entsize == bed->s->sizeof_rela)
1970 swap_in = bed->s->swap_reloca_in;
1971 else
1973 bfd_set_error (bfd_error_wrong_format);
1974 return FALSE;
1977 erela = external_relocs;
1978 erelaend = erela + shdr->sh_size;
1979 irela = internal_relocs;
1980 while (erela < erelaend)
1982 bfd_vma r_symndx;
1984 (*swap_in) (abfd, erela, irela);
1985 r_symndx = ELF32_R_SYM (irela->r_info);
1986 if (bed->s->arch_size == 64)
1987 r_symndx >>= 24;
1988 if ((size_t) r_symndx >= nsyms)
1990 (*_bfd_error_handler)
1991 (_("%B: bad reloc symbol index (0x%lx >= 0x%lx)"
1992 " for offset 0x%lx in section `%A'"),
1993 abfd, sec,
1994 (unsigned long) r_symndx, (unsigned long) nsyms, irela->r_offset);
1995 bfd_set_error (bfd_error_bad_value);
1996 return FALSE;
1998 irela += bed->s->int_rels_per_ext_rel;
1999 erela += shdr->sh_entsize;
2002 return TRUE;
2005 /* Read and swap the relocs for a section O. They may have been
2006 cached. If the EXTERNAL_RELOCS and INTERNAL_RELOCS arguments are
2007 not NULL, they are used as buffers to read into. They are known to
2008 be large enough. If the INTERNAL_RELOCS relocs argument is NULL,
2009 the return value is allocated using either malloc or bfd_alloc,
2010 according to the KEEP_MEMORY argument. If O has two relocation
2011 sections (both REL and RELA relocations), then the REL_HDR
2012 relocations will appear first in INTERNAL_RELOCS, followed by the
2013 REL_HDR2 relocations. */
2015 Elf_Internal_Rela *
2016 _bfd_elf_link_read_relocs (bfd *abfd,
2017 asection *o,
2018 void *external_relocs,
2019 Elf_Internal_Rela *internal_relocs,
2020 bfd_boolean keep_memory)
2022 Elf_Internal_Shdr *rel_hdr;
2023 void *alloc1 = NULL;
2024 Elf_Internal_Rela *alloc2 = NULL;
2025 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
2027 if (elf_section_data (o)->relocs != NULL)
2028 return elf_section_data (o)->relocs;
2030 if (o->reloc_count == 0)
2031 return NULL;
2033 rel_hdr = &elf_section_data (o)->rel_hdr;
2035 if (internal_relocs == NULL)
2037 bfd_size_type size;
2039 size = o->reloc_count;
2040 size *= bed->s->int_rels_per_ext_rel * sizeof (Elf_Internal_Rela);
2041 if (keep_memory)
2042 internal_relocs = bfd_alloc (abfd, size);
2043 else
2044 internal_relocs = alloc2 = bfd_malloc (size);
2045 if (internal_relocs == NULL)
2046 goto error_return;
2049 if (external_relocs == NULL)
2051 bfd_size_type size = rel_hdr->sh_size;
2053 if (elf_section_data (o)->rel_hdr2)
2054 size += elf_section_data (o)->rel_hdr2->sh_size;
2055 alloc1 = bfd_malloc (size);
2056 if (alloc1 == NULL)
2057 goto error_return;
2058 external_relocs = alloc1;
2061 if (!elf_link_read_relocs_from_section (abfd, o, rel_hdr,
2062 external_relocs,
2063 internal_relocs))
2064 goto error_return;
2065 if (elf_section_data (o)->rel_hdr2
2066 && (!elf_link_read_relocs_from_section
2067 (abfd, o,
2068 elf_section_data (o)->rel_hdr2,
2069 ((bfd_byte *) external_relocs) + rel_hdr->sh_size,
2070 internal_relocs + (NUM_SHDR_ENTRIES (rel_hdr)
2071 * bed->s->int_rels_per_ext_rel))))
2072 goto error_return;
2074 /* Cache the results for next time, if we can. */
2075 if (keep_memory)
2076 elf_section_data (o)->relocs = internal_relocs;
2078 if (alloc1 != NULL)
2079 free (alloc1);
2081 /* Don't free alloc2, since if it was allocated we are passing it
2082 back (under the name of internal_relocs). */
2084 return internal_relocs;
2086 error_return:
2087 if (alloc1 != NULL)
2088 free (alloc1);
2089 if (alloc2 != NULL)
2090 free (alloc2);
2091 return NULL;
2094 /* Compute the size of, and allocate space for, REL_HDR which is the
2095 section header for a section containing relocations for O. */
2097 bfd_boolean
2098 _bfd_elf_link_size_reloc_section (bfd *abfd,
2099 Elf_Internal_Shdr *rel_hdr,
2100 asection *o)
2102 bfd_size_type reloc_count;
2103 bfd_size_type num_rel_hashes;
2105 /* Figure out how many relocations there will be. */
2106 if (rel_hdr == &elf_section_data (o)->rel_hdr)
2107 reloc_count = elf_section_data (o)->rel_count;
2108 else
2109 reloc_count = elf_section_data (o)->rel_count2;
2111 num_rel_hashes = o->reloc_count;
2112 if (num_rel_hashes < reloc_count)
2113 num_rel_hashes = reloc_count;
2115 /* That allows us to calculate the size of the section. */
2116 rel_hdr->sh_size = rel_hdr->sh_entsize * reloc_count;
2118 /* The contents field must last into write_object_contents, so we
2119 allocate it with bfd_alloc rather than malloc. Also since we
2120 cannot be sure that the contents will actually be filled in,
2121 we zero the allocated space. */
2122 rel_hdr->contents = bfd_zalloc (abfd, rel_hdr->sh_size);
2123 if (rel_hdr->contents == NULL && rel_hdr->sh_size != 0)
2124 return FALSE;
2126 /* We only allocate one set of hash entries, so we only do it the
2127 first time we are called. */
2128 if (elf_section_data (o)->rel_hashes == NULL
2129 && num_rel_hashes)
2131 struct elf_link_hash_entry **p;
2133 p = bfd_zmalloc (num_rel_hashes * sizeof (struct elf_link_hash_entry *));
2134 if (p == NULL)
2135 return FALSE;
2137 elf_section_data (o)->rel_hashes = p;
2140 return TRUE;
2143 /* Copy the relocations indicated by the INTERNAL_RELOCS (which
2144 originated from the section given by INPUT_REL_HDR) to the
2145 OUTPUT_BFD. */
2147 bfd_boolean
2148 _bfd_elf_link_output_relocs (bfd *output_bfd,
2149 asection *input_section,
2150 Elf_Internal_Shdr *input_rel_hdr,
2151 Elf_Internal_Rela *internal_relocs,
2152 struct elf_link_hash_entry **rel_hash
2153 ATTRIBUTE_UNUSED)
2155 Elf_Internal_Rela *irela;
2156 Elf_Internal_Rela *irelaend;
2157 bfd_byte *erel;
2158 Elf_Internal_Shdr *output_rel_hdr;
2159 asection *output_section;
2160 unsigned int *rel_countp = NULL;
2161 const struct elf_backend_data *bed;
2162 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
2164 output_section = input_section->output_section;
2165 output_rel_hdr = NULL;
2167 if (elf_section_data (output_section)->rel_hdr.sh_entsize
2168 == input_rel_hdr->sh_entsize)
2170 output_rel_hdr = &elf_section_data (output_section)->rel_hdr;
2171 rel_countp = &elf_section_data (output_section)->rel_count;
2173 else if (elf_section_data (output_section)->rel_hdr2
2174 && (elf_section_data (output_section)->rel_hdr2->sh_entsize
2175 == input_rel_hdr->sh_entsize))
2177 output_rel_hdr = elf_section_data (output_section)->rel_hdr2;
2178 rel_countp = &elf_section_data (output_section)->rel_count2;
2180 else
2182 (*_bfd_error_handler)
2183 (_("%B: relocation size mismatch in %B section %A"),
2184 output_bfd, input_section->owner, input_section);
2185 bfd_set_error (bfd_error_wrong_object_format);
2186 return FALSE;
2189 bed = get_elf_backend_data (output_bfd);
2190 if (input_rel_hdr->sh_entsize == bed->s->sizeof_rel)
2191 swap_out = bed->s->swap_reloc_out;
2192 else if (input_rel_hdr->sh_entsize == bed->s->sizeof_rela)
2193 swap_out = bed->s->swap_reloca_out;
2194 else
2195 abort ();
2197 erel = output_rel_hdr->contents;
2198 erel += *rel_countp * input_rel_hdr->sh_entsize;
2199 irela = internal_relocs;
2200 irelaend = irela + (NUM_SHDR_ENTRIES (input_rel_hdr)
2201 * bed->s->int_rels_per_ext_rel);
2202 while (irela < irelaend)
2204 (*swap_out) (output_bfd, irela, erel);
2205 irela += bed->s->int_rels_per_ext_rel;
2206 erel += input_rel_hdr->sh_entsize;
2209 /* Bump the counter, so that we know where to add the next set of
2210 relocations. */
2211 *rel_countp += NUM_SHDR_ENTRIES (input_rel_hdr);
2213 return TRUE;
2216 /* Make weak undefined symbols in PIE dynamic. */
2218 bfd_boolean
2219 _bfd_elf_link_hash_fixup_symbol (struct bfd_link_info *info,
2220 struct elf_link_hash_entry *h)
2222 if (info->pie
2223 && h->dynindx == -1
2224 && h->root.type == bfd_link_hash_undefweak)
2225 return bfd_elf_link_record_dynamic_symbol (info, h);
2227 return TRUE;
2230 /* Fix up the flags for a symbol. This handles various cases which
2231 can only be fixed after all the input files are seen. This is
2232 currently called by both adjust_dynamic_symbol and
2233 assign_sym_version, which is unnecessary but perhaps more robust in
2234 the face of future changes. */
2236 bfd_boolean
2237 _bfd_elf_fix_symbol_flags (struct elf_link_hash_entry *h,
2238 struct elf_info_failed *eif)
2240 const struct elf_backend_data *bed = NULL;
2242 /* If this symbol was mentioned in a non-ELF file, try to set
2243 DEF_REGULAR and REF_REGULAR correctly. This is the only way to
2244 permit a non-ELF file to correctly refer to a symbol defined in
2245 an ELF dynamic object. */
2246 if (h->non_elf)
2248 while (h->root.type == bfd_link_hash_indirect)
2249 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2251 if (h->root.type != bfd_link_hash_defined
2252 && h->root.type != bfd_link_hash_defweak)
2254 h->ref_regular = 1;
2255 h->ref_regular_nonweak = 1;
2257 else
2259 if (h->root.u.def.section->owner != NULL
2260 && (bfd_get_flavour (h->root.u.def.section->owner)
2261 == bfd_target_elf_flavour))
2263 h->ref_regular = 1;
2264 h->ref_regular_nonweak = 1;
2266 else
2267 h->def_regular = 1;
2270 if (h->dynindx == -1
2271 && (h->def_dynamic
2272 || h->ref_dynamic))
2274 if (! bfd_elf_link_record_dynamic_symbol (eif->info, h))
2276 eif->failed = TRUE;
2277 return FALSE;
2281 else
2283 /* Unfortunately, NON_ELF is only correct if the symbol
2284 was first seen in a non-ELF file. Fortunately, if the symbol
2285 was first seen in an ELF file, we're probably OK unless the
2286 symbol was defined in a non-ELF file. Catch that case here.
2287 FIXME: We're still in trouble if the symbol was first seen in
2288 a dynamic object, and then later in a non-ELF regular object. */
2289 if ((h->root.type == bfd_link_hash_defined
2290 || h->root.type == bfd_link_hash_defweak)
2291 && !h->def_regular
2292 && (h->root.u.def.section->owner != NULL
2293 ? (bfd_get_flavour (h->root.u.def.section->owner)
2294 != bfd_target_elf_flavour)
2295 : (bfd_is_abs_section (h->root.u.def.section)
2296 && !h->def_dynamic)))
2297 h->def_regular = 1;
2300 /* Backend specific symbol fixup. */
2301 if (elf_hash_table (eif->info)->dynobj)
2303 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2304 if (bed->elf_backend_fixup_symbol
2305 && !(*bed->elf_backend_fixup_symbol) (eif->info, h))
2306 return FALSE;
2309 /* If this is a final link, and the symbol was defined as a common
2310 symbol in a regular object file, and there was no definition in
2311 any dynamic object, then the linker will have allocated space for
2312 the symbol in a common section but the DEF_REGULAR
2313 flag will not have been set. */
2314 if (h->root.type == bfd_link_hash_defined
2315 && !h->def_regular
2316 && h->ref_regular
2317 && !h->def_dynamic
2318 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
2319 h->def_regular = 1;
2321 /* If -Bsymbolic was used (which means to bind references to global
2322 symbols to the definition within the shared object), and this
2323 symbol was defined in a regular object, then it actually doesn't
2324 need a PLT entry. Likewise, if the symbol has non-default
2325 visibility. If the symbol has hidden or internal visibility, we
2326 will force it local. */
2327 if (h->needs_plt
2328 && eif->info->shared
2329 && is_elf_hash_table (eif->info->hash)
2330 && (eif->info->symbolic
2331 || ELF_ST_VISIBILITY (h->other) != STV_DEFAULT)
2332 && h->def_regular)
2334 bfd_boolean force_local;
2336 force_local = (ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
2337 || ELF_ST_VISIBILITY (h->other) == STV_HIDDEN);
2338 (*bed->elf_backend_hide_symbol) (eif->info, h, force_local);
2341 /* If a weak undefined symbol has non-default visibility, we also
2342 hide it from the dynamic linker. */
2343 if (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT
2344 && h->root.type == bfd_link_hash_undefweak)
2346 const struct elf_backend_data *bed;
2347 bed = get_elf_backend_data (elf_hash_table (eif->info)->dynobj);
2348 (*bed->elf_backend_hide_symbol) (eif->info, h, TRUE);
2351 /* If this is a weak defined symbol in a dynamic object, and we know
2352 the real definition in the dynamic object, copy interesting flags
2353 over to the real definition. */
2354 if (h->u.weakdef != NULL)
2356 struct elf_link_hash_entry *weakdef;
2358 weakdef = h->u.weakdef;
2359 if (h->root.type == bfd_link_hash_indirect)
2360 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2362 BFD_ASSERT (h->root.type == bfd_link_hash_defined
2363 || h->root.type == bfd_link_hash_defweak);
2364 BFD_ASSERT (weakdef->root.type == bfd_link_hash_defined
2365 || weakdef->root.type == bfd_link_hash_defweak);
2366 BFD_ASSERT (weakdef->def_dynamic);
2368 /* If the real definition is defined by a regular object file,
2369 don't do anything special. See the longer description in
2370 _bfd_elf_adjust_dynamic_symbol, below. */
2371 if (weakdef->def_regular)
2372 h->u.weakdef = NULL;
2373 else
2374 (*bed->elf_backend_copy_indirect_symbol) (eif->info, weakdef,
2378 return TRUE;
2381 /* Make the backend pick a good value for a dynamic symbol. This is
2382 called via elf_link_hash_traverse, and also calls itself
2383 recursively. */
2385 bfd_boolean
2386 _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data)
2388 struct elf_info_failed *eif = data;
2389 bfd *dynobj;
2390 const struct elf_backend_data *bed;
2392 if (! is_elf_hash_table (eif->info->hash))
2393 return FALSE;
2395 if (h->root.type == bfd_link_hash_warning)
2397 h->got = elf_hash_table (eif->info)->init_got_offset;
2398 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2400 /* When warning symbols are created, they **replace** the "real"
2401 entry in the hash table, thus we never get to see the real
2402 symbol in a hash traversal. So look at it now. */
2403 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2406 /* Ignore indirect symbols. These are added by the versioning code. */
2407 if (h->root.type == bfd_link_hash_indirect)
2408 return TRUE;
2410 /* Fix the symbol flags. */
2411 if (! _bfd_elf_fix_symbol_flags (h, eif))
2412 return FALSE;
2414 /* If this symbol does not require a PLT entry, and it is not
2415 defined by a dynamic object, or is not referenced by a regular
2416 object, ignore it. We do have to handle a weak defined symbol,
2417 even if no regular object refers to it, if we decided to add it
2418 to the dynamic symbol table. FIXME: Do we normally need to worry
2419 about symbols which are defined by one dynamic object and
2420 referenced by another one? */
2421 if (!h->needs_plt
2422 && (h->def_regular
2423 || !h->def_dynamic
2424 || (!h->ref_regular
2425 && (h->u.weakdef == NULL || h->u.weakdef->dynindx == -1))))
2427 h->plt = elf_hash_table (eif->info)->init_plt_offset;
2428 return TRUE;
2431 /* If we've already adjusted this symbol, don't do it again. This
2432 can happen via a recursive call. */
2433 if (h->dynamic_adjusted)
2434 return TRUE;
2436 /* Don't look at this symbol again. Note that we must set this
2437 after checking the above conditions, because we may look at a
2438 symbol once, decide not to do anything, and then get called
2439 recursively later after REF_REGULAR is set below. */
2440 h->dynamic_adjusted = 1;
2442 /* If this is a weak definition, and we know a real definition, and
2443 the real symbol is not itself defined by a regular object file,
2444 then get a good value for the real definition. We handle the
2445 real symbol first, for the convenience of the backend routine.
2447 Note that there is a confusing case here. If the real definition
2448 is defined by a regular object file, we don't get the real symbol
2449 from the dynamic object, but we do get the weak symbol. If the
2450 processor backend uses a COPY reloc, then if some routine in the
2451 dynamic object changes the real symbol, we will not see that
2452 change in the corresponding weak symbol. This is the way other
2453 ELF linkers work as well, and seems to be a result of the shared
2454 library model.
2456 I will clarify this issue. Most SVR4 shared libraries define the
2457 variable _timezone and define timezone as a weak synonym. The
2458 tzset call changes _timezone. If you write
2459 extern int timezone;
2460 int _timezone = 5;
2461 int main () { tzset (); printf ("%d %d\n", timezone, _timezone); }
2462 you might expect that, since timezone is a synonym for _timezone,
2463 the same number will print both times. However, if the processor
2464 backend uses a COPY reloc, then actually timezone will be copied
2465 into your process image, and, since you define _timezone
2466 yourself, _timezone will not. Thus timezone and _timezone will
2467 wind up at different memory locations. The tzset call will set
2468 _timezone, leaving timezone unchanged. */
2470 if (h->u.weakdef != NULL)
2472 /* If we get to this point, we know there is an implicit
2473 reference by a regular object file via the weak symbol H.
2474 FIXME: Is this really true? What if the traversal finds
2475 H->U.WEAKDEF before it finds H? */
2476 h->u.weakdef->ref_regular = 1;
2478 if (! _bfd_elf_adjust_dynamic_symbol (h->u.weakdef, eif))
2479 return FALSE;
2482 /* If a symbol has no type and no size and does not require a PLT
2483 entry, then we are probably about to do the wrong thing here: we
2484 are probably going to create a COPY reloc for an empty object.
2485 This case can arise when a shared object is built with assembly
2486 code, and the assembly code fails to set the symbol type. */
2487 if (h->size == 0
2488 && h->type == STT_NOTYPE
2489 && !h->needs_plt)
2490 (*_bfd_error_handler)
2491 (_("warning: type and size of dynamic symbol `%s' are not defined"),
2492 h->root.root.string);
2494 dynobj = elf_hash_table (eif->info)->dynobj;
2495 bed = get_elf_backend_data (dynobj);
2496 if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h))
2498 eif->failed = TRUE;
2499 return FALSE;
2502 return TRUE;
2505 /* Adjust all external symbols pointing into SEC_MERGE sections
2506 to reflect the object merging within the sections. */
2508 bfd_boolean
2509 _bfd_elf_link_sec_merge_syms (struct elf_link_hash_entry *h, void *data)
2511 asection *sec;
2513 if (h->root.type == bfd_link_hash_warning)
2514 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2516 if ((h->root.type == bfd_link_hash_defined
2517 || h->root.type == bfd_link_hash_defweak)
2518 && ((sec = h->root.u.def.section)->flags & SEC_MERGE)
2519 && sec->sec_info_type == ELF_INFO_TYPE_MERGE)
2521 bfd *output_bfd = data;
2523 h->root.u.def.value =
2524 _bfd_merged_section_offset (output_bfd,
2525 &h->root.u.def.section,
2526 elf_section_data (sec)->sec_info,
2527 h->root.u.def.value);
2530 return TRUE;
2533 /* Returns false if the symbol referred to by H should be considered
2534 to resolve local to the current module, and true if it should be
2535 considered to bind dynamically. */
2537 bfd_boolean
2538 _bfd_elf_dynamic_symbol_p (struct elf_link_hash_entry *h,
2539 struct bfd_link_info *info,
2540 bfd_boolean ignore_protected)
2542 bfd_boolean binding_stays_local_p;
2544 if (h == NULL)
2545 return FALSE;
2547 while (h->root.type == bfd_link_hash_indirect
2548 || h->root.type == bfd_link_hash_warning)
2549 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2551 /* If it was forced local, then clearly it's not dynamic. */
2552 if (h->dynindx == -1)
2553 return FALSE;
2554 if (h->forced_local)
2555 return FALSE;
2557 /* Identify the cases where name binding rules say that a
2558 visible symbol resolves locally. */
2559 binding_stays_local_p = info->executable || info->symbolic;
2561 switch (ELF_ST_VISIBILITY (h->other))
2563 case STV_INTERNAL:
2564 case STV_HIDDEN:
2565 return FALSE;
2567 case STV_PROTECTED:
2568 /* Proper resolution for function pointer equality may require
2569 that these symbols perhaps be resolved dynamically, even though
2570 we should be resolving them to the current module. */
2571 if (!ignore_protected || h->type != STT_FUNC)
2572 binding_stays_local_p = TRUE;
2573 break;
2575 default:
2576 break;
2579 /* If it isn't defined locally, then clearly it's dynamic. */
2580 if (!h->def_regular)
2581 return TRUE;
2583 /* Otherwise, the symbol is dynamic if binding rules don't tell
2584 us that it remains local. */
2585 return !binding_stays_local_p;
2588 /* Return true if the symbol referred to by H should be considered
2589 to resolve local to the current module, and false otherwise. Differs
2590 from (the inverse of) _bfd_elf_dynamic_symbol_p in the treatment of
2591 undefined symbols and weak symbols. */
2593 bfd_boolean
2594 _bfd_elf_symbol_refs_local_p (struct elf_link_hash_entry *h,
2595 struct bfd_link_info *info,
2596 bfd_boolean local_protected)
2598 /* If it's a local sym, of course we resolve locally. */
2599 if (h == NULL)
2600 return TRUE;
2602 /* Common symbols that become definitions don't get the DEF_REGULAR
2603 flag set, so test it first, and don't bail out. */
2604 if (ELF_COMMON_DEF_P (h))
2605 /* Do nothing. */;
2606 /* If we don't have a definition in a regular file, then we can't
2607 resolve locally. The sym is either undefined or dynamic. */
2608 else if (!h->def_regular)
2609 return FALSE;
2611 /* Forced local symbols resolve locally. */
2612 if (h->forced_local)
2613 return TRUE;
2615 /* As do non-dynamic symbols. */
2616 if (h->dynindx == -1)
2617 return TRUE;
2619 /* At this point, we know the symbol is defined and dynamic. In an
2620 executable it must resolve locally, likewise when building symbolic
2621 shared libraries. */
2622 if (info->executable || info->symbolic)
2623 return TRUE;
2625 /* Now deal with defined dynamic symbols in shared libraries. Ones
2626 with default visibility might not resolve locally. */
2627 if (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT)
2628 return FALSE;
2630 /* However, STV_HIDDEN or STV_INTERNAL ones must be local. */
2631 if (ELF_ST_VISIBILITY (h->other) != STV_PROTECTED)
2632 return TRUE;
2634 /* STV_PROTECTED non-function symbols are local. */
2635 if (h->type != STT_FUNC)
2636 return TRUE;
2638 /* Function pointer equality tests may require that STV_PROTECTED
2639 symbols be treated as dynamic symbols, even when we know that the
2640 dynamic linker will resolve them locally. */
2641 return local_protected;
2644 /* Caches some TLS segment info, and ensures that the TLS segment vma is
2645 aligned. Returns the first TLS output section. */
2647 struct bfd_section *
2648 _bfd_elf_tls_setup (bfd *obfd, struct bfd_link_info *info)
2650 struct bfd_section *sec, *tls;
2651 unsigned int align = 0;
2653 for (sec = obfd->sections; sec != NULL; sec = sec->next)
2654 if ((sec->flags & SEC_THREAD_LOCAL) != 0)
2655 break;
2656 tls = sec;
2658 for (; sec != NULL && (sec->flags & SEC_THREAD_LOCAL) != 0; sec = sec->next)
2659 if (sec->alignment_power > align)
2660 align = sec->alignment_power;
2662 elf_hash_table (info)->tls_sec = tls;
2664 /* Ensure the alignment of the first section is the largest alignment,
2665 so that the tls segment starts aligned. */
2666 if (tls != NULL)
2667 tls->alignment_power = align;
2669 return tls;
2672 /* Return TRUE iff this is a non-common, definition of a non-function symbol. */
2673 static bfd_boolean
2674 is_global_data_symbol_definition (bfd *abfd ATTRIBUTE_UNUSED,
2675 Elf_Internal_Sym *sym)
2677 const struct elf_backend_data *bed;
2679 /* Local symbols do not count, but target specific ones might. */
2680 if (ELF_ST_BIND (sym->st_info) != STB_GLOBAL
2681 && ELF_ST_BIND (sym->st_info) < STB_LOOS)
2682 return FALSE;
2684 /* Function symbols do not count. */
2685 if (ELF_ST_TYPE (sym->st_info) == STT_FUNC)
2686 return FALSE;
2688 /* If the section is undefined, then so is the symbol. */
2689 if (sym->st_shndx == SHN_UNDEF)
2690 return FALSE;
2692 /* If the symbol is defined in the common section, then
2693 it is a common definition and so does not count. */
2694 bed = get_elf_backend_data (abfd);
2695 if (bed->common_definition (sym))
2696 return FALSE;
2698 /* If the symbol is in a target specific section then we
2699 must rely upon the backend to tell us what it is. */
2700 if (sym->st_shndx >= SHN_LORESERVE && sym->st_shndx < SHN_ABS)
2701 /* FIXME - this function is not coded yet:
2703 return _bfd_is_global_symbol_definition (abfd, sym);
2705 Instead for now assume that the definition is not global,
2706 Even if this is wrong, at least the linker will behave
2707 in the same way that it used to do. */
2708 return FALSE;
2710 return TRUE;
2713 /* Search the symbol table of the archive element of the archive ABFD
2714 whose archive map contains a mention of SYMDEF, and determine if
2715 the symbol is defined in this element. */
2716 static bfd_boolean
2717 elf_link_is_defined_archive_symbol (bfd * abfd, carsym * symdef)
2719 Elf_Internal_Shdr * hdr;
2720 bfd_size_type symcount;
2721 bfd_size_type extsymcount;
2722 bfd_size_type extsymoff;
2723 Elf_Internal_Sym *isymbuf;
2724 Elf_Internal_Sym *isym;
2725 Elf_Internal_Sym *isymend;
2726 bfd_boolean result;
2728 abfd = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
2729 if (abfd == NULL)
2730 return FALSE;
2732 if (! bfd_check_format (abfd, bfd_object))
2733 return FALSE;
2735 /* If we have already included the element containing this symbol in the
2736 link then we do not need to include it again. Just claim that any symbol
2737 it contains is not a definition, so that our caller will not decide to
2738 (re)include this element. */
2739 if (abfd->archive_pass)
2740 return FALSE;
2742 /* Select the appropriate symbol table. */
2743 if ((abfd->flags & DYNAMIC) == 0 || elf_dynsymtab (abfd) == 0)
2744 hdr = &elf_tdata (abfd)->symtab_hdr;
2745 else
2746 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
2748 symcount = hdr->sh_size / get_elf_backend_data (abfd)->s->sizeof_sym;
2750 /* The sh_info field of the symtab header tells us where the
2751 external symbols start. We don't care about the local symbols. */
2752 if (elf_bad_symtab (abfd))
2754 extsymcount = symcount;
2755 extsymoff = 0;
2757 else
2759 extsymcount = symcount - hdr->sh_info;
2760 extsymoff = hdr->sh_info;
2763 if (extsymcount == 0)
2764 return FALSE;
2766 /* Read in the symbol table. */
2767 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
2768 NULL, NULL, NULL);
2769 if (isymbuf == NULL)
2770 return FALSE;
2772 /* Scan the symbol table looking for SYMDEF. */
2773 result = FALSE;
2774 for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++)
2776 const char *name;
2778 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
2779 isym->st_name);
2780 if (name == NULL)
2781 break;
2783 if (strcmp (name, symdef->name) == 0)
2785 result = is_global_data_symbol_definition (abfd, isym);
2786 break;
2790 free (isymbuf);
2792 return result;
2795 /* Add an entry to the .dynamic table. */
2797 bfd_boolean
2798 _bfd_elf_add_dynamic_entry (struct bfd_link_info *info,
2799 bfd_vma tag,
2800 bfd_vma val)
2802 struct elf_link_hash_table *hash_table;
2803 const struct elf_backend_data *bed;
2804 asection *s;
2805 bfd_size_type newsize;
2806 bfd_byte *newcontents;
2807 Elf_Internal_Dyn dyn;
2809 hash_table = elf_hash_table (info);
2810 if (! is_elf_hash_table (hash_table))
2811 return FALSE;
2813 if (info->warn_shared_textrel && info->shared && tag == DT_TEXTREL)
2814 _bfd_error_handler
2815 (_("warning: creating a DT_TEXTREL in a shared object."));
2817 bed = get_elf_backend_data (hash_table->dynobj);
2818 s = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2819 BFD_ASSERT (s != NULL);
2821 newsize = s->size + bed->s->sizeof_dyn;
2822 newcontents = bfd_realloc (s->contents, newsize);
2823 if (newcontents == NULL)
2824 return FALSE;
2826 dyn.d_tag = tag;
2827 dyn.d_un.d_val = val;
2828 bed->s->swap_dyn_out (hash_table->dynobj, &dyn, newcontents + s->size);
2830 s->size = newsize;
2831 s->contents = newcontents;
2833 return TRUE;
2836 /* Add a DT_NEEDED entry for this dynamic object if DO_IT is true,
2837 otherwise just check whether one already exists. Returns -1 on error,
2838 1 if a DT_NEEDED tag already exists, and 0 on success. */
2840 static int
2841 elf_add_dt_needed_tag (bfd *abfd,
2842 struct bfd_link_info *info,
2843 const char *soname,
2844 bfd_boolean do_it)
2846 struct elf_link_hash_table *hash_table;
2847 bfd_size_type oldsize;
2848 bfd_size_type strindex;
2850 if (!_bfd_elf_link_create_dynstrtab (abfd, info))
2851 return -1;
2853 hash_table = elf_hash_table (info);
2854 oldsize = _bfd_elf_strtab_size (hash_table->dynstr);
2855 strindex = _bfd_elf_strtab_add (hash_table->dynstr, soname, FALSE);
2856 if (strindex == (bfd_size_type) -1)
2857 return -1;
2859 if (oldsize == _bfd_elf_strtab_size (hash_table->dynstr))
2861 asection *sdyn;
2862 const struct elf_backend_data *bed;
2863 bfd_byte *extdyn;
2865 bed = get_elf_backend_data (hash_table->dynobj);
2866 sdyn = bfd_get_section_by_name (hash_table->dynobj, ".dynamic");
2867 if (sdyn != NULL)
2868 for (extdyn = sdyn->contents;
2869 extdyn < sdyn->contents + sdyn->size;
2870 extdyn += bed->s->sizeof_dyn)
2872 Elf_Internal_Dyn dyn;
2874 bed->s->swap_dyn_in (hash_table->dynobj, extdyn, &dyn);
2875 if (dyn.d_tag == DT_NEEDED
2876 && dyn.d_un.d_val == strindex)
2878 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2879 return 1;
2884 if (do_it)
2886 if (!_bfd_elf_link_create_dynamic_sections (hash_table->dynobj, info))
2887 return -1;
2889 if (!_bfd_elf_add_dynamic_entry (info, DT_NEEDED, strindex))
2890 return -1;
2892 else
2893 /* We were just checking for existence of the tag. */
2894 _bfd_elf_strtab_delref (hash_table->dynstr, strindex);
2896 return 0;
2899 /* Sort symbol by value and section. */
2900 static int
2901 elf_sort_symbol (const void *arg1, const void *arg2)
2903 const struct elf_link_hash_entry *h1;
2904 const struct elf_link_hash_entry *h2;
2905 bfd_signed_vma vdiff;
2907 h1 = *(const struct elf_link_hash_entry **) arg1;
2908 h2 = *(const struct elf_link_hash_entry **) arg2;
2909 vdiff = h1->root.u.def.value - h2->root.u.def.value;
2910 if (vdiff != 0)
2911 return vdiff > 0 ? 1 : -1;
2912 else
2914 long sdiff = h1->root.u.def.section->id - h2->root.u.def.section->id;
2915 if (sdiff != 0)
2916 return sdiff > 0 ? 1 : -1;
2918 return 0;
2921 /* This function is used to adjust offsets into .dynstr for
2922 dynamic symbols. This is called via elf_link_hash_traverse. */
2924 static bfd_boolean
2925 elf_adjust_dynstr_offsets (struct elf_link_hash_entry *h, void *data)
2927 struct elf_strtab_hash *dynstr = data;
2929 if (h->root.type == bfd_link_hash_warning)
2930 h = (struct elf_link_hash_entry *) h->root.u.i.link;
2932 if (h->dynindx != -1)
2933 h->dynstr_index = _bfd_elf_strtab_offset (dynstr, h->dynstr_index);
2934 return TRUE;
2937 /* Assign string offsets in .dynstr, update all structures referencing
2938 them. */
2940 static bfd_boolean
2941 elf_finalize_dynstr (bfd *output_bfd, struct bfd_link_info *info)
2943 struct elf_link_hash_table *hash_table = elf_hash_table (info);
2944 struct elf_link_local_dynamic_entry *entry;
2945 struct elf_strtab_hash *dynstr = hash_table->dynstr;
2946 bfd *dynobj = hash_table->dynobj;
2947 asection *sdyn;
2948 bfd_size_type size;
2949 const struct elf_backend_data *bed;
2950 bfd_byte *extdyn;
2952 _bfd_elf_strtab_finalize (dynstr);
2953 size = _bfd_elf_strtab_size (dynstr);
2955 bed = get_elf_backend_data (dynobj);
2956 sdyn = bfd_get_section_by_name (dynobj, ".dynamic");
2957 BFD_ASSERT (sdyn != NULL);
2959 /* Update all .dynamic entries referencing .dynstr strings. */
2960 for (extdyn = sdyn->contents;
2961 extdyn < sdyn->contents + sdyn->size;
2962 extdyn += bed->s->sizeof_dyn)
2964 Elf_Internal_Dyn dyn;
2966 bed->s->swap_dyn_in (dynobj, extdyn, &dyn);
2967 switch (dyn.d_tag)
2969 case DT_STRSZ:
2970 dyn.d_un.d_val = size;
2971 break;
2972 case DT_NEEDED:
2973 case DT_SONAME:
2974 case DT_RPATH:
2975 case DT_RUNPATH:
2976 case DT_FILTER:
2977 case DT_AUXILIARY:
2978 dyn.d_un.d_val = _bfd_elf_strtab_offset (dynstr, dyn.d_un.d_val);
2979 break;
2980 default:
2981 continue;
2983 bed->s->swap_dyn_out (dynobj, &dyn, extdyn);
2986 /* Now update local dynamic symbols. */
2987 for (entry = hash_table->dynlocal; entry ; entry = entry->next)
2988 entry->isym.st_name = _bfd_elf_strtab_offset (dynstr,
2989 entry->isym.st_name);
2991 /* And the rest of dynamic symbols. */
2992 elf_link_hash_traverse (hash_table, elf_adjust_dynstr_offsets, dynstr);
2994 /* Adjust version definitions. */
2995 if (elf_tdata (output_bfd)->cverdefs)
2997 asection *s;
2998 bfd_byte *p;
2999 bfd_size_type i;
3000 Elf_Internal_Verdef def;
3001 Elf_Internal_Verdaux defaux;
3003 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
3004 p = s->contents;
3007 _bfd_elf_swap_verdef_in (output_bfd, (Elf_External_Verdef *) p,
3008 &def);
3009 p += sizeof (Elf_External_Verdef);
3010 if (def.vd_aux != sizeof (Elf_External_Verdef))
3011 continue;
3012 for (i = 0; i < def.vd_cnt; ++i)
3014 _bfd_elf_swap_verdaux_in (output_bfd,
3015 (Elf_External_Verdaux *) p, &defaux);
3016 defaux.vda_name = _bfd_elf_strtab_offset (dynstr,
3017 defaux.vda_name);
3018 _bfd_elf_swap_verdaux_out (output_bfd,
3019 &defaux, (Elf_External_Verdaux *) p);
3020 p += sizeof (Elf_External_Verdaux);
3023 while (def.vd_next);
3026 /* Adjust version references. */
3027 if (elf_tdata (output_bfd)->verref)
3029 asection *s;
3030 bfd_byte *p;
3031 bfd_size_type i;
3032 Elf_Internal_Verneed need;
3033 Elf_Internal_Vernaux needaux;
3035 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
3036 p = s->contents;
3039 _bfd_elf_swap_verneed_in (output_bfd, (Elf_External_Verneed *) p,
3040 &need);
3041 need.vn_file = _bfd_elf_strtab_offset (dynstr, need.vn_file);
3042 _bfd_elf_swap_verneed_out (output_bfd, &need,
3043 (Elf_External_Verneed *) p);
3044 p += sizeof (Elf_External_Verneed);
3045 for (i = 0; i < need.vn_cnt; ++i)
3047 _bfd_elf_swap_vernaux_in (output_bfd,
3048 (Elf_External_Vernaux *) p, &needaux);
3049 needaux.vna_name = _bfd_elf_strtab_offset (dynstr,
3050 needaux.vna_name);
3051 _bfd_elf_swap_vernaux_out (output_bfd,
3052 &needaux,
3053 (Elf_External_Vernaux *) p);
3054 p += sizeof (Elf_External_Vernaux);
3057 while (need.vn_next);
3060 return TRUE;
3063 /* Add symbols from an ELF object file to the linker hash table. */
3065 static bfd_boolean
3066 elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info)
3068 Elf_Internal_Shdr *hdr;
3069 bfd_size_type symcount;
3070 bfd_size_type extsymcount;
3071 bfd_size_type extsymoff;
3072 struct elf_link_hash_entry **sym_hash;
3073 bfd_boolean dynamic;
3074 Elf_External_Versym *extversym = NULL;
3075 Elf_External_Versym *ever;
3076 struct elf_link_hash_entry *weaks;
3077 struct elf_link_hash_entry **nondeflt_vers = NULL;
3078 bfd_size_type nondeflt_vers_cnt = 0;
3079 Elf_Internal_Sym *isymbuf = NULL;
3080 Elf_Internal_Sym *isym;
3081 Elf_Internal_Sym *isymend;
3082 const struct elf_backend_data *bed;
3083 bfd_boolean add_needed;
3084 struct elf_link_hash_table *htab;
3085 bfd_size_type amt;
3086 void *alloc_mark = NULL;
3087 void *old_tab = NULL;
3088 void *old_hash;
3089 void *old_ent;
3090 struct bfd_link_hash_entry *old_undefs = NULL;
3091 struct bfd_link_hash_entry *old_undefs_tail = NULL;
3092 long old_dynsymcount = 0;
3093 size_t tabsize = 0;
3094 size_t hashsize = 0;
3096 htab = elf_hash_table (info);
3097 bed = get_elf_backend_data (abfd);
3099 if ((abfd->flags & DYNAMIC) == 0)
3100 dynamic = FALSE;
3101 else
3103 dynamic = TRUE;
3105 /* You can't use -r against a dynamic object. Also, there's no
3106 hope of using a dynamic object which does not exactly match
3107 the format of the output file. */
3108 if (info->relocatable
3109 || !is_elf_hash_table (htab)
3110 || htab->root.creator != abfd->xvec)
3112 if (info->relocatable)
3113 bfd_set_error (bfd_error_invalid_operation);
3114 else
3115 bfd_set_error (bfd_error_wrong_format);
3116 goto error_return;
3120 /* As a GNU extension, any input sections which are named
3121 .gnu.warning.SYMBOL are treated as warning symbols for the given
3122 symbol. This differs from .gnu.warning sections, which generate
3123 warnings when they are included in an output file. */
3124 if (info->executable)
3126 asection *s;
3128 for (s = abfd->sections; s != NULL; s = s->next)
3130 const char *name;
3132 name = bfd_get_section_name (abfd, s);
3133 if (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) == 0)
3135 char *msg;
3136 bfd_size_type sz;
3138 name += sizeof ".gnu.warning." - 1;
3140 /* If this is a shared object, then look up the symbol
3141 in the hash table. If it is there, and it is already
3142 been defined, then we will not be using the entry
3143 from this shared object, so we don't need to warn.
3144 FIXME: If we see the definition in a regular object
3145 later on, we will warn, but we shouldn't. The only
3146 fix is to keep track of what warnings we are supposed
3147 to emit, and then handle them all at the end of the
3148 link. */
3149 if (dynamic)
3151 struct elf_link_hash_entry *h;
3153 h = elf_link_hash_lookup (htab, name, FALSE, FALSE, TRUE);
3155 /* FIXME: What about bfd_link_hash_common? */
3156 if (h != NULL
3157 && (h->root.type == bfd_link_hash_defined
3158 || h->root.type == bfd_link_hash_defweak))
3160 /* We don't want to issue this warning. Clobber
3161 the section size so that the warning does not
3162 get copied into the output file. */
3163 s->size = 0;
3164 continue;
3168 sz = s->size;
3169 msg = bfd_alloc (abfd, sz + 1);
3170 if (msg == NULL)
3171 goto error_return;
3173 if (! bfd_get_section_contents (abfd, s, msg, 0, sz))
3174 goto error_return;
3176 msg[sz] = '\0';
3178 if (! (_bfd_generic_link_add_one_symbol
3179 (info, abfd, name, BSF_WARNING, s, 0, msg,
3180 FALSE, bed->collect, NULL)))
3181 goto error_return;
3183 if (! info->relocatable)
3185 /* Clobber the section size so that the warning does
3186 not get copied into the output file. */
3187 s->size = 0;
3189 /* Also set SEC_EXCLUDE, so that symbols defined in
3190 the warning section don't get copied to the output. */
3191 s->flags |= SEC_EXCLUDE;
3197 add_needed = TRUE;
3198 if (! dynamic)
3200 /* If we are creating a shared library, create all the dynamic
3201 sections immediately. We need to attach them to something,
3202 so we attach them to this BFD, provided it is the right
3203 format. FIXME: If there are no input BFD's of the same
3204 format as the output, we can't make a shared library. */
3205 if (info->shared
3206 && is_elf_hash_table (htab)
3207 && htab->root.creator == abfd->xvec
3208 && !htab->dynamic_sections_created)
3210 if (! _bfd_elf_link_create_dynamic_sections (abfd, info))
3211 goto error_return;
3214 else if (!is_elf_hash_table (htab))
3215 goto error_return;
3216 else
3218 asection *s;
3219 const char *soname = NULL;
3220 struct bfd_link_needed_list *rpath = NULL, *runpath = NULL;
3221 int ret;
3223 /* ld --just-symbols and dynamic objects don't mix very well.
3224 ld shouldn't allow it. */
3225 if ((s = abfd->sections) != NULL
3226 && s->sec_info_type == ELF_INFO_TYPE_JUST_SYMS)
3227 abort ();
3229 /* If this dynamic lib was specified on the command line with
3230 --as-needed in effect, then we don't want to add a DT_NEEDED
3231 tag unless the lib is actually used. Similary for libs brought
3232 in by another lib's DT_NEEDED. When --no-add-needed is used
3233 on a dynamic lib, we don't want to add a DT_NEEDED entry for
3234 any dynamic library in DT_NEEDED tags in the dynamic lib at
3235 all. */
3236 add_needed = (elf_dyn_lib_class (abfd)
3237 & (DYN_AS_NEEDED | DYN_DT_NEEDED
3238 | DYN_NO_NEEDED)) == 0;
3240 s = bfd_get_section_by_name (abfd, ".dynamic");
3241 if (s != NULL)
3243 bfd_byte *dynbuf;
3244 bfd_byte *extdyn;
3245 int elfsec;
3246 unsigned long shlink;
3248 if (!bfd_malloc_and_get_section (abfd, s, &dynbuf))
3249 goto error_free_dyn;
3251 elfsec = _bfd_elf_section_from_bfd_section (abfd, s);
3252 if (elfsec == -1)
3253 goto error_free_dyn;
3254 shlink = elf_elfsections (abfd)[elfsec]->sh_link;
3256 for (extdyn = dynbuf;
3257 extdyn < dynbuf + s->size;
3258 extdyn += bed->s->sizeof_dyn)
3260 Elf_Internal_Dyn dyn;
3262 bed->s->swap_dyn_in (abfd, extdyn, &dyn);
3263 if (dyn.d_tag == DT_SONAME)
3265 unsigned int tagv = dyn.d_un.d_val;
3266 soname = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3267 if (soname == NULL)
3268 goto error_free_dyn;
3270 if (dyn.d_tag == DT_NEEDED)
3272 struct bfd_link_needed_list *n, **pn;
3273 char *fnm, *anm;
3274 unsigned int tagv = dyn.d_un.d_val;
3276 amt = sizeof (struct bfd_link_needed_list);
3277 n = bfd_alloc (abfd, amt);
3278 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3279 if (n == NULL || fnm == NULL)
3280 goto error_free_dyn;
3281 amt = strlen (fnm) + 1;
3282 anm = bfd_alloc (abfd, amt);
3283 if (anm == NULL)
3284 goto error_free_dyn;
3285 memcpy (anm, fnm, amt);
3286 n->name = anm;
3287 n->by = abfd;
3288 n->next = NULL;
3289 for (pn = &htab->needed; *pn != NULL; pn = &(*pn)->next)
3291 *pn = n;
3293 if (dyn.d_tag == DT_RUNPATH)
3295 struct bfd_link_needed_list *n, **pn;
3296 char *fnm, *anm;
3297 unsigned int tagv = dyn.d_un.d_val;
3299 amt = sizeof (struct bfd_link_needed_list);
3300 n = bfd_alloc (abfd, amt);
3301 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3302 if (n == NULL || fnm == NULL)
3303 goto error_free_dyn;
3304 amt = strlen (fnm) + 1;
3305 anm = bfd_alloc (abfd, amt);
3306 if (anm == NULL)
3307 goto error_free_dyn;
3308 memcpy (anm, fnm, amt);
3309 n->name = anm;
3310 n->by = abfd;
3311 n->next = NULL;
3312 for (pn = & runpath;
3313 *pn != NULL;
3314 pn = &(*pn)->next)
3316 *pn = n;
3318 /* Ignore DT_RPATH if we have seen DT_RUNPATH. */
3319 if (!runpath && dyn.d_tag == DT_RPATH)
3321 struct bfd_link_needed_list *n, **pn;
3322 char *fnm, *anm;
3323 unsigned int tagv = dyn.d_un.d_val;
3325 amt = sizeof (struct bfd_link_needed_list);
3326 n = bfd_alloc (abfd, amt);
3327 fnm = bfd_elf_string_from_elf_section (abfd, shlink, tagv);
3328 if (n == NULL || fnm == NULL)
3329 goto error_free_dyn;
3330 amt = strlen (fnm) + 1;
3331 anm = bfd_alloc (abfd, amt);
3332 if (anm == NULL)
3334 error_free_dyn:
3335 free (dynbuf);
3336 goto error_return;
3338 memcpy (anm, fnm, amt);
3339 n->name = anm;
3340 n->by = abfd;
3341 n->next = NULL;
3342 for (pn = & rpath;
3343 *pn != NULL;
3344 pn = &(*pn)->next)
3346 *pn = n;
3350 free (dynbuf);
3353 /* DT_RUNPATH overrides DT_RPATH. Do _NOT_ bfd_release, as that
3354 frees all more recently bfd_alloc'd blocks as well. */
3355 if (runpath)
3356 rpath = runpath;
3358 if (rpath)
3360 struct bfd_link_needed_list **pn;
3361 for (pn = &htab->runpath; *pn != NULL; pn = &(*pn)->next)
3363 *pn = rpath;
3366 /* We do not want to include any of the sections in a dynamic
3367 object in the output file. We hack by simply clobbering the
3368 list of sections in the BFD. This could be handled more
3369 cleanly by, say, a new section flag; the existing
3370 SEC_NEVER_LOAD flag is not the one we want, because that one
3371 still implies that the section takes up space in the output
3372 file. */
3373 bfd_section_list_clear (abfd);
3375 /* Find the name to use in a DT_NEEDED entry that refers to this
3376 object. If the object has a DT_SONAME entry, we use it.
3377 Otherwise, if the generic linker stuck something in
3378 elf_dt_name, we use that. Otherwise, we just use the file
3379 name. */
3380 if (soname == NULL || *soname == '\0')
3382 soname = elf_dt_name (abfd);
3383 if (soname == NULL || *soname == '\0')
3384 soname = bfd_get_filename (abfd);
3387 /* Save the SONAME because sometimes the linker emulation code
3388 will need to know it. */
3389 elf_dt_name (abfd) = soname;
3391 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
3392 if (ret < 0)
3393 goto error_return;
3395 /* If we have already included this dynamic object in the
3396 link, just ignore it. There is no reason to include a
3397 particular dynamic object more than once. */
3398 if (ret > 0)
3399 return TRUE;
3402 /* If this is a dynamic object, we always link against the .dynsym
3403 symbol table, not the .symtab symbol table. The dynamic linker
3404 will only see the .dynsym symbol table, so there is no reason to
3405 look at .symtab for a dynamic object. */
3407 if (! dynamic || elf_dynsymtab (abfd) == 0)
3408 hdr = &elf_tdata (abfd)->symtab_hdr;
3409 else
3410 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
3412 symcount = hdr->sh_size / bed->s->sizeof_sym;
3414 /* The sh_info field of the symtab header tells us where the
3415 external symbols start. We don't care about the local symbols at
3416 this point. */
3417 if (elf_bad_symtab (abfd))
3419 extsymcount = symcount;
3420 extsymoff = 0;
3422 else
3424 extsymcount = symcount - hdr->sh_info;
3425 extsymoff = hdr->sh_info;
3428 sym_hash = NULL;
3429 if (extsymcount != 0)
3431 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, extsymcount, extsymoff,
3432 NULL, NULL, NULL);
3433 if (isymbuf == NULL)
3434 goto error_return;
3436 /* We store a pointer to the hash table entry for each external
3437 symbol. */
3438 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
3439 sym_hash = bfd_alloc (abfd, amt);
3440 if (sym_hash == NULL)
3441 goto error_free_sym;
3442 elf_sym_hashes (abfd) = sym_hash;
3445 if (dynamic)
3447 /* Read in any version definitions. */
3448 if (!_bfd_elf_slurp_version_tables (abfd,
3449 info->default_imported_symver))
3450 goto error_free_sym;
3452 /* Read in the symbol versions, but don't bother to convert them
3453 to internal format. */
3454 if (elf_dynversym (abfd) != 0)
3456 Elf_Internal_Shdr *versymhdr;
3458 versymhdr = &elf_tdata (abfd)->dynversym_hdr;
3459 extversym = bfd_malloc (versymhdr->sh_size);
3460 if (extversym == NULL)
3461 goto error_free_sym;
3462 amt = versymhdr->sh_size;
3463 if (bfd_seek (abfd, versymhdr->sh_offset, SEEK_SET) != 0
3464 || bfd_bread (extversym, amt, abfd) != amt)
3465 goto error_free_vers;
3469 /* If we are loading an as-needed shared lib, save the symbol table
3470 state before we start adding symbols. If the lib turns out
3471 to be unneeded, restore the state. */
3472 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
3474 unsigned int i;
3475 size_t entsize;
3477 for (entsize = 0, i = 0; i < htab->root.table.size; i++)
3479 struct bfd_hash_entry *p;
3480 struct elf_link_hash_entry *h;
3482 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3484 h = (struct elf_link_hash_entry *) p;
3485 entsize += htab->root.table.entsize;
3486 if (h->root.type == bfd_link_hash_warning)
3487 entsize += htab->root.table.entsize;
3491 tabsize = htab->root.table.size * sizeof (struct bfd_hash_entry *);
3492 hashsize = extsymcount * sizeof (struct elf_link_hash_entry *);
3493 old_tab = bfd_malloc (tabsize + entsize + hashsize);
3494 if (old_tab == NULL)
3495 goto error_free_vers;
3497 /* Remember the current objalloc pointer, so that all mem for
3498 symbols added can later be reclaimed. */
3499 alloc_mark = bfd_hash_allocate (&htab->root.table, 1);
3500 if (alloc_mark == NULL)
3501 goto error_free_vers;
3503 /* Clone the symbol table and sym hashes. Remember some
3504 pointers into the symbol table, and dynamic symbol count. */
3505 old_hash = (char *) old_tab + tabsize;
3506 old_ent = (char *) old_hash + hashsize;
3507 memcpy (old_tab, htab->root.table.table, tabsize);
3508 memcpy (old_hash, sym_hash, hashsize);
3509 old_undefs = htab->root.undefs;
3510 old_undefs_tail = htab->root.undefs_tail;
3511 old_dynsymcount = htab->dynsymcount;
3513 for (i = 0; i < htab->root.table.size; i++)
3515 struct bfd_hash_entry *p;
3516 struct elf_link_hash_entry *h;
3518 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
3520 memcpy (old_ent, p, htab->root.table.entsize);
3521 old_ent = (char *) old_ent + htab->root.table.entsize;
3522 h = (struct elf_link_hash_entry *) p;
3523 if (h->root.type == bfd_link_hash_warning)
3525 memcpy (old_ent, h->root.u.i.link, htab->root.table.entsize);
3526 old_ent = (char *) old_ent + htab->root.table.entsize;
3532 weaks = NULL;
3533 ever = extversym != NULL ? extversym + extsymoff : NULL;
3534 for (isym = isymbuf, isymend = isymbuf + extsymcount;
3535 isym < isymend;
3536 isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL))
3538 int bind;
3539 bfd_vma value;
3540 asection *sec, *new_sec;
3541 flagword flags;
3542 const char *name;
3543 struct elf_link_hash_entry *h;
3544 bfd_boolean definition;
3545 bfd_boolean size_change_ok;
3546 bfd_boolean type_change_ok;
3547 bfd_boolean new_weakdef;
3548 bfd_boolean override;
3549 bfd_boolean common;
3550 unsigned int old_alignment;
3551 bfd *old_bfd;
3553 override = FALSE;
3555 flags = BSF_NO_FLAGS;
3556 sec = NULL;
3557 value = isym->st_value;
3558 *sym_hash = NULL;
3559 common = bed->common_definition (isym);
3561 bind = ELF_ST_BIND (isym->st_info);
3562 if (bind == STB_LOCAL)
3564 /* This should be impossible, since ELF requires that all
3565 global symbols follow all local symbols, and that sh_info
3566 point to the first global symbol. Unfortunately, Irix 5
3567 screws this up. */
3568 continue;
3570 else if (bind == STB_GLOBAL)
3572 if (isym->st_shndx != SHN_UNDEF && !common)
3573 flags = BSF_GLOBAL;
3575 else if (bind == STB_WEAK)
3576 flags = BSF_WEAK;
3577 else
3579 /* Leave it up to the processor backend. */
3582 if (isym->st_shndx == SHN_UNDEF)
3583 sec = bfd_und_section_ptr;
3584 else if (isym->st_shndx < SHN_LORESERVE
3585 || isym->st_shndx > SHN_HIRESERVE)
3587 sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
3588 if (sec == NULL)
3589 sec = bfd_abs_section_ptr;
3590 else if (sec->kept_section)
3592 /* Symbols from discarded section are undefined, and have
3593 default visibility. */
3594 sec = bfd_und_section_ptr;
3595 isym->st_shndx = SHN_UNDEF;
3596 isym->st_other = (STV_DEFAULT
3597 | (isym->st_other & ~ ELF_ST_VISIBILITY (-1)));
3599 else if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
3600 value -= sec->vma;
3602 else if (isym->st_shndx == SHN_ABS)
3603 sec = bfd_abs_section_ptr;
3604 else if (isym->st_shndx == SHN_COMMON)
3606 sec = bfd_com_section_ptr;
3607 /* What ELF calls the size we call the value. What ELF
3608 calls the value we call the alignment. */
3609 value = isym->st_size;
3611 else
3613 /* Leave it up to the processor backend. */
3616 name = bfd_elf_string_from_elf_section (abfd, hdr->sh_link,
3617 isym->st_name);
3618 if (name == NULL)
3619 goto error_free_vers;
3621 if (isym->st_shndx == SHN_COMMON
3622 && ELF_ST_TYPE (isym->st_info) == STT_TLS)
3624 asection *tcomm = bfd_get_section_by_name (abfd, ".tcommon");
3626 if (tcomm == NULL)
3628 tcomm = bfd_make_section_with_flags (abfd, ".tcommon",
3629 (SEC_ALLOC
3630 | SEC_IS_COMMON
3631 | SEC_LINKER_CREATED
3632 | SEC_THREAD_LOCAL));
3633 if (tcomm == NULL)
3634 goto error_free_vers;
3636 sec = tcomm;
3638 else if (bed->elf_add_symbol_hook)
3640 if (! (*bed->elf_add_symbol_hook) (abfd, info, isym, &name, &flags,
3641 &sec, &value))
3642 goto error_free_vers;
3644 /* The hook function sets the name to NULL if this symbol
3645 should be skipped for some reason. */
3646 if (name == NULL)
3647 continue;
3650 /* Sanity check that all possibilities were handled. */
3651 if (sec == NULL)
3653 bfd_set_error (bfd_error_bad_value);
3654 goto error_free_vers;
3657 if (bfd_is_und_section (sec)
3658 || bfd_is_com_section (sec))
3659 definition = FALSE;
3660 else
3661 definition = TRUE;
3663 size_change_ok = FALSE;
3664 type_change_ok = bed->type_change_ok;
3665 old_alignment = 0;
3666 old_bfd = NULL;
3667 new_sec = sec;
3669 if (is_elf_hash_table (htab))
3671 Elf_Internal_Versym iver;
3672 unsigned int vernum = 0;
3673 bfd_boolean skip;
3675 if (ever == NULL)
3677 if (info->default_imported_symver)
3678 /* Use the default symbol version created earlier. */
3679 iver.vs_vers = elf_tdata (abfd)->cverdefs;
3680 else
3681 iver.vs_vers = 0;
3683 else
3684 _bfd_elf_swap_versym_in (abfd, ever, &iver);
3686 vernum = iver.vs_vers & VERSYM_VERSION;
3688 /* If this is a hidden symbol, or if it is not version
3689 1, we append the version name to the symbol name.
3690 However, we do not modify a non-hidden absolute symbol
3691 if it is not a function, because it might be the version
3692 symbol itself. FIXME: What if it isn't? */
3693 if ((iver.vs_vers & VERSYM_HIDDEN) != 0
3694 || (vernum > 1 && (! bfd_is_abs_section (sec)
3695 || ELF_ST_TYPE (isym->st_info) == STT_FUNC)))
3697 const char *verstr;
3698 size_t namelen, verlen, newlen;
3699 char *newname, *p;
3701 if (isym->st_shndx != SHN_UNDEF)
3703 if (vernum > elf_tdata (abfd)->cverdefs)
3704 verstr = NULL;
3705 else if (vernum > 1)
3706 verstr =
3707 elf_tdata (abfd)->verdef[vernum - 1].vd_nodename;
3708 else
3709 verstr = "";
3711 if (verstr == NULL)
3713 (*_bfd_error_handler)
3714 (_("%B: %s: invalid version %u (max %d)"),
3715 abfd, name, vernum,
3716 elf_tdata (abfd)->cverdefs);
3717 bfd_set_error (bfd_error_bad_value);
3718 goto error_free_vers;
3721 else
3723 /* We cannot simply test for the number of
3724 entries in the VERNEED section since the
3725 numbers for the needed versions do not start
3726 at 0. */
3727 Elf_Internal_Verneed *t;
3729 verstr = NULL;
3730 for (t = elf_tdata (abfd)->verref;
3731 t != NULL;
3732 t = t->vn_nextref)
3734 Elf_Internal_Vernaux *a;
3736 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
3738 if (a->vna_other == vernum)
3740 verstr = a->vna_nodename;
3741 break;
3744 if (a != NULL)
3745 break;
3747 if (verstr == NULL)
3749 (*_bfd_error_handler)
3750 (_("%B: %s: invalid needed version %d"),
3751 abfd, name, vernum);
3752 bfd_set_error (bfd_error_bad_value);
3753 goto error_free_vers;
3757 namelen = strlen (name);
3758 verlen = strlen (verstr);
3759 newlen = namelen + verlen + 2;
3760 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3761 && isym->st_shndx != SHN_UNDEF)
3762 ++newlen;
3764 newname = bfd_hash_allocate (&htab->root.table, newlen);
3765 if (newname == NULL)
3766 goto error_free_vers;
3767 memcpy (newname, name, namelen);
3768 p = newname + namelen;
3769 *p++ = ELF_VER_CHR;
3770 /* If this is a defined non-hidden version symbol,
3771 we add another @ to the name. This indicates the
3772 default version of the symbol. */
3773 if ((iver.vs_vers & VERSYM_HIDDEN) == 0
3774 && isym->st_shndx != SHN_UNDEF)
3775 *p++ = ELF_VER_CHR;
3776 memcpy (p, verstr, verlen + 1);
3778 name = newname;
3781 if (!_bfd_elf_merge_symbol (abfd, info, name, isym, &sec,
3782 &value, &old_alignment,
3783 sym_hash, &skip, &override,
3784 &type_change_ok, &size_change_ok))
3785 goto error_free_vers;
3787 if (skip)
3788 continue;
3790 if (override)
3791 definition = FALSE;
3793 h = *sym_hash;
3794 while (h->root.type == bfd_link_hash_indirect
3795 || h->root.type == bfd_link_hash_warning)
3796 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3798 /* Remember the old alignment if this is a common symbol, so
3799 that we don't reduce the alignment later on. We can't
3800 check later, because _bfd_generic_link_add_one_symbol
3801 will set a default for the alignment which we want to
3802 override. We also remember the old bfd where the existing
3803 definition comes from. */
3804 switch (h->root.type)
3806 default:
3807 break;
3809 case bfd_link_hash_defined:
3810 case bfd_link_hash_defweak:
3811 old_bfd = h->root.u.def.section->owner;
3812 break;
3814 case bfd_link_hash_common:
3815 old_bfd = h->root.u.c.p->section->owner;
3816 old_alignment = h->root.u.c.p->alignment_power;
3817 break;
3820 if (elf_tdata (abfd)->verdef != NULL
3821 && ! override
3822 && vernum > 1
3823 && definition)
3824 h->verinfo.verdef = &elf_tdata (abfd)->verdef[vernum - 1];
3827 if (! (_bfd_generic_link_add_one_symbol
3828 (info, abfd, name, flags, sec, value, NULL, FALSE, bed->collect,
3829 (struct bfd_link_hash_entry **) sym_hash)))
3830 goto error_free_vers;
3832 h = *sym_hash;
3833 while (h->root.type == bfd_link_hash_indirect
3834 || h->root.type == bfd_link_hash_warning)
3835 h = (struct elf_link_hash_entry *) h->root.u.i.link;
3836 *sym_hash = h;
3838 new_weakdef = FALSE;
3839 if (dynamic
3840 && definition
3841 && (flags & BSF_WEAK) != 0
3842 && ELF_ST_TYPE (isym->st_info) != STT_FUNC
3843 && is_elf_hash_table (htab)
3844 && h->u.weakdef == NULL)
3846 /* Keep a list of all weak defined non function symbols from
3847 a dynamic object, using the weakdef field. Later in this
3848 function we will set the weakdef field to the correct
3849 value. We only put non-function symbols from dynamic
3850 objects on this list, because that happens to be the only
3851 time we need to know the normal symbol corresponding to a
3852 weak symbol, and the information is time consuming to
3853 figure out. If the weakdef field is not already NULL,
3854 then this symbol was already defined by some previous
3855 dynamic object, and we will be using that previous
3856 definition anyhow. */
3858 h->u.weakdef = weaks;
3859 weaks = h;
3860 new_weakdef = TRUE;
3863 /* Set the alignment of a common symbol. */
3864 if ((common || bfd_is_com_section (sec))
3865 && h->root.type == bfd_link_hash_common)
3867 unsigned int align;
3869 if (common)
3870 align = bfd_log2 (isym->st_value);
3871 else
3873 /* The new symbol is a common symbol in a shared object.
3874 We need to get the alignment from the section. */
3875 align = new_sec->alignment_power;
3877 if (align > old_alignment
3878 /* Permit an alignment power of zero if an alignment of one
3879 is specified and no other alignments have been specified. */
3880 || (isym->st_value == 1 && old_alignment == 0))
3881 h->root.u.c.p->alignment_power = align;
3882 else
3883 h->root.u.c.p->alignment_power = old_alignment;
3886 if (is_elf_hash_table (htab))
3888 bfd_boolean dynsym;
3890 /* Check the alignment when a common symbol is involved. This
3891 can change when a common symbol is overridden by a normal
3892 definition or a common symbol is ignored due to the old
3893 normal definition. We need to make sure the maximum
3894 alignment is maintained. */
3895 if ((old_alignment || common)
3896 && h->root.type != bfd_link_hash_common)
3898 unsigned int common_align;
3899 unsigned int normal_align;
3900 unsigned int symbol_align;
3901 bfd *normal_bfd;
3902 bfd *common_bfd;
3904 symbol_align = ffs (h->root.u.def.value) - 1;
3905 if (h->root.u.def.section->owner != NULL
3906 && (h->root.u.def.section->owner->flags & DYNAMIC) == 0)
3908 normal_align = h->root.u.def.section->alignment_power;
3909 if (normal_align > symbol_align)
3910 normal_align = symbol_align;
3912 else
3913 normal_align = symbol_align;
3915 if (old_alignment)
3917 common_align = old_alignment;
3918 common_bfd = old_bfd;
3919 normal_bfd = abfd;
3921 else
3923 common_align = bfd_log2 (isym->st_value);
3924 common_bfd = abfd;
3925 normal_bfd = old_bfd;
3928 if (normal_align < common_align)
3929 (*_bfd_error_handler)
3930 (_("Warning: alignment %u of symbol `%s' in %B"
3931 " is smaller than %u in %B"),
3932 normal_bfd, common_bfd,
3933 1 << normal_align, name, 1 << common_align);
3936 /* Remember the symbol size and type. */
3937 if (isym->st_size != 0
3938 && (definition || h->size == 0))
3940 if (h->size != 0 && h->size != isym->st_size && ! size_change_ok)
3941 (*_bfd_error_handler)
3942 (_("Warning: size of symbol `%s' changed"
3943 " from %lu in %B to %lu in %B"),
3944 old_bfd, abfd,
3945 name, (unsigned long) h->size,
3946 (unsigned long) isym->st_size);
3948 h->size = isym->st_size;
3951 /* If this is a common symbol, then we always want H->SIZE
3952 to be the size of the common symbol. The code just above
3953 won't fix the size if a common symbol becomes larger. We
3954 don't warn about a size change here, because that is
3955 covered by --warn-common. */
3956 if (h->root.type == bfd_link_hash_common)
3957 h->size = h->root.u.c.size;
3959 if (ELF_ST_TYPE (isym->st_info) != STT_NOTYPE
3960 && (definition || h->type == STT_NOTYPE))
3962 if (h->type != STT_NOTYPE
3963 && h->type != ELF_ST_TYPE (isym->st_info)
3964 && ! type_change_ok)
3965 (*_bfd_error_handler)
3966 (_("Warning: type of symbol `%s' changed"
3967 " from %d to %d in %B"),
3968 abfd, name, h->type, ELF_ST_TYPE (isym->st_info));
3970 h->type = ELF_ST_TYPE (isym->st_info);
3973 /* If st_other has a processor-specific meaning, specific
3974 code might be needed here. We never merge the visibility
3975 attribute with the one from a dynamic object. */
3976 if (bed->elf_backend_merge_symbol_attribute)
3977 (*bed->elf_backend_merge_symbol_attribute) (h, isym, definition,
3978 dynamic);
3980 /* If this symbol has default visibility and the user has requested
3981 we not re-export it, then mark it as hidden. */
3982 if (definition && !dynamic
3983 && (abfd->no_export
3984 || (abfd->my_archive && abfd->my_archive->no_export))
3985 && ELF_ST_VISIBILITY (isym->st_other) != STV_INTERNAL)
3986 isym->st_other = (STV_HIDDEN
3987 | (isym->st_other & ~ELF_ST_VISIBILITY (-1)));
3989 if (isym->st_other != 0 && !dynamic)
3991 unsigned char hvis, symvis, other, nvis;
3993 /* Take the balance of OTHER from the definition. */
3994 other = (definition ? isym->st_other : h->other);
3995 other &= ~ ELF_ST_VISIBILITY (-1);
3997 /* Combine visibilities, using the most constraining one. */
3998 hvis = ELF_ST_VISIBILITY (h->other);
3999 symvis = ELF_ST_VISIBILITY (isym->st_other);
4000 if (! hvis)
4001 nvis = symvis;
4002 else if (! symvis)
4003 nvis = hvis;
4004 else
4005 nvis = hvis < symvis ? hvis : symvis;
4007 h->other = other | nvis;
4010 /* Set a flag in the hash table entry indicating the type of
4011 reference or definition we just found. Keep a count of
4012 the number of dynamic symbols we find. A dynamic symbol
4013 is one which is referenced or defined by both a regular
4014 object and a shared object. */
4015 dynsym = FALSE;
4016 if (! dynamic)
4018 if (! definition)
4020 h->ref_regular = 1;
4021 if (bind != STB_WEAK)
4022 h->ref_regular_nonweak = 1;
4024 else
4025 h->def_regular = 1;
4026 if (! info->executable
4027 || h->def_dynamic
4028 || h->ref_dynamic)
4029 dynsym = TRUE;
4031 else
4033 if (! definition)
4034 h->ref_dynamic = 1;
4035 else
4036 h->def_dynamic = 1;
4037 if (h->def_regular
4038 || h->ref_regular
4039 || (h->u.weakdef != NULL
4040 && ! new_weakdef
4041 && h->u.weakdef->dynindx != -1))
4042 dynsym = TRUE;
4045 /* Check to see if we need to add an indirect symbol for
4046 the default name. */
4047 if (definition || h->root.type == bfd_link_hash_common)
4048 if (!_bfd_elf_add_default_symbol (abfd, info, h, name, isym,
4049 &sec, &value, &dynsym,
4050 override))
4051 goto error_free_vers;
4053 if (definition && !dynamic)
4055 char *p = strchr (name, ELF_VER_CHR);
4056 if (p != NULL && p[1] != ELF_VER_CHR)
4058 /* Queue non-default versions so that .symver x, x@FOO
4059 aliases can be checked. */
4060 if (!nondeflt_vers)
4062 amt = ((isymend - isym + 1)
4063 * sizeof (struct elf_link_hash_entry *));
4064 nondeflt_vers = bfd_malloc (amt);
4066 nondeflt_vers[nondeflt_vers_cnt++] = h;
4070 if (dynsym && h->dynindx == -1)
4072 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4073 goto error_free_vers;
4074 if (h->u.weakdef != NULL
4075 && ! new_weakdef
4076 && h->u.weakdef->dynindx == -1)
4078 if (!bfd_elf_link_record_dynamic_symbol (info, h->u.weakdef))
4079 goto error_free_vers;
4082 else if (dynsym && h->dynindx != -1)
4083 /* If the symbol already has a dynamic index, but
4084 visibility says it should not be visible, turn it into
4085 a local symbol. */
4086 switch (ELF_ST_VISIBILITY (h->other))
4088 case STV_INTERNAL:
4089 case STV_HIDDEN:
4090 (*bed->elf_backend_hide_symbol) (info, h, TRUE);
4091 dynsym = FALSE;
4092 break;
4095 if (!add_needed
4096 && definition
4097 && dynsym
4098 && h->ref_regular)
4100 int ret;
4101 const char *soname = elf_dt_name (abfd);
4103 /* A symbol from a library loaded via DT_NEEDED of some
4104 other library is referenced by a regular object.
4105 Add a DT_NEEDED entry for it. Issue an error if
4106 --no-add-needed is used. */
4107 if ((elf_dyn_lib_class (abfd) & DYN_NO_NEEDED) != 0)
4109 (*_bfd_error_handler)
4110 (_("%s: invalid DSO for symbol `%s' definition"),
4111 abfd, name);
4112 bfd_set_error (bfd_error_bad_value);
4113 goto error_free_vers;
4116 elf_dyn_lib_class (abfd) &= ~DYN_AS_NEEDED;
4118 add_needed = TRUE;
4119 ret = elf_add_dt_needed_tag (abfd, info, soname, add_needed);
4120 if (ret < 0)
4121 goto error_free_vers;
4123 BFD_ASSERT (ret == 0);
4128 if (extversym != NULL)
4130 free (extversym);
4131 extversym = NULL;
4134 if (isymbuf != NULL)
4136 free (isymbuf);
4137 isymbuf = NULL;
4140 if ((elf_dyn_lib_class (abfd) & DYN_AS_NEEDED) != 0)
4142 unsigned int i;
4144 /* Restore the symbol table. */
4145 old_hash = (char *) old_tab + tabsize;
4146 old_ent = (char *) old_hash + hashsize;
4147 sym_hash = elf_sym_hashes (abfd);
4148 memcpy (htab->root.table.table, old_tab, tabsize);
4149 memcpy (sym_hash, old_hash, hashsize);
4150 htab->root.undefs = old_undefs;
4151 htab->root.undefs_tail = old_undefs_tail;
4152 for (i = 0; i < htab->root.table.size; i++)
4154 struct bfd_hash_entry *p;
4155 struct elf_link_hash_entry *h;
4157 for (p = htab->root.table.table[i]; p != NULL; p = p->next)
4159 h = (struct elf_link_hash_entry *) p;
4160 if (h->root.type == bfd_link_hash_warning)
4161 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4162 if (h->dynindx >= old_dynsymcount)
4163 _bfd_elf_strtab_delref (htab->dynstr, h->dynstr_index);
4165 memcpy (p, old_ent, htab->root.table.entsize);
4166 old_ent = (char *) old_ent + htab->root.table.entsize;
4167 h = (struct elf_link_hash_entry *) p;
4168 if (h->root.type == bfd_link_hash_warning)
4170 memcpy (h->root.u.i.link, old_ent, htab->root.table.entsize);
4171 old_ent = (char *) old_ent + htab->root.table.entsize;
4176 free (old_tab);
4177 objalloc_free_block ((struct objalloc *) htab->root.table.memory,
4178 alloc_mark);
4179 if (nondeflt_vers != NULL)
4180 free (nondeflt_vers);
4181 return TRUE;
4184 if (old_tab != NULL)
4186 free (old_tab);
4187 old_tab = NULL;
4190 /* Now that all the symbols from this input file are created, handle
4191 .symver foo, foo@BAR such that any relocs against foo become foo@BAR. */
4192 if (nondeflt_vers != NULL)
4194 bfd_size_type cnt, symidx;
4196 for (cnt = 0; cnt < nondeflt_vers_cnt; ++cnt)
4198 struct elf_link_hash_entry *h = nondeflt_vers[cnt], *hi;
4199 char *shortname, *p;
4201 p = strchr (h->root.root.string, ELF_VER_CHR);
4202 if (p == NULL
4203 || (h->root.type != bfd_link_hash_defined
4204 && h->root.type != bfd_link_hash_defweak))
4205 continue;
4207 amt = p - h->root.root.string;
4208 shortname = bfd_malloc (amt + 1);
4209 memcpy (shortname, h->root.root.string, amt);
4210 shortname[amt] = '\0';
4212 hi = (struct elf_link_hash_entry *)
4213 bfd_link_hash_lookup (&htab->root, shortname,
4214 FALSE, FALSE, FALSE);
4215 if (hi != NULL
4216 && hi->root.type == h->root.type
4217 && hi->root.u.def.value == h->root.u.def.value
4218 && hi->root.u.def.section == h->root.u.def.section)
4220 (*bed->elf_backend_hide_symbol) (info, hi, TRUE);
4221 hi->root.type = bfd_link_hash_indirect;
4222 hi->root.u.i.link = (struct bfd_link_hash_entry *) h;
4223 (*bed->elf_backend_copy_indirect_symbol) (info, h, hi);
4224 sym_hash = elf_sym_hashes (abfd);
4225 if (sym_hash)
4226 for (symidx = 0; symidx < extsymcount; ++symidx)
4227 if (sym_hash[symidx] == hi)
4229 sym_hash[symidx] = h;
4230 break;
4233 free (shortname);
4235 free (nondeflt_vers);
4236 nondeflt_vers = NULL;
4239 /* Now set the weakdefs field correctly for all the weak defined
4240 symbols we found. The only way to do this is to search all the
4241 symbols. Since we only need the information for non functions in
4242 dynamic objects, that's the only time we actually put anything on
4243 the list WEAKS. We need this information so that if a regular
4244 object refers to a symbol defined weakly in a dynamic object, the
4245 real symbol in the dynamic object is also put in the dynamic
4246 symbols; we also must arrange for both symbols to point to the
4247 same memory location. We could handle the general case of symbol
4248 aliasing, but a general symbol alias can only be generated in
4249 assembler code, handling it correctly would be very time
4250 consuming, and other ELF linkers don't handle general aliasing
4251 either. */
4252 if (weaks != NULL)
4254 struct elf_link_hash_entry **hpp;
4255 struct elf_link_hash_entry **hppend;
4256 struct elf_link_hash_entry **sorted_sym_hash;
4257 struct elf_link_hash_entry *h;
4258 size_t sym_count;
4260 /* Since we have to search the whole symbol list for each weak
4261 defined symbol, search time for N weak defined symbols will be
4262 O(N^2). Binary search will cut it down to O(NlogN). */
4263 amt = extsymcount * sizeof (struct elf_link_hash_entry *);
4264 sorted_sym_hash = bfd_malloc (amt);
4265 if (sorted_sym_hash == NULL)
4266 goto error_return;
4267 sym_hash = sorted_sym_hash;
4268 hpp = elf_sym_hashes (abfd);
4269 hppend = hpp + extsymcount;
4270 sym_count = 0;
4271 for (; hpp < hppend; hpp++)
4273 h = *hpp;
4274 if (h != NULL
4275 && h->root.type == bfd_link_hash_defined
4276 && h->type != STT_FUNC)
4278 *sym_hash = h;
4279 sym_hash++;
4280 sym_count++;
4284 qsort (sorted_sym_hash, sym_count,
4285 sizeof (struct elf_link_hash_entry *),
4286 elf_sort_symbol);
4288 while (weaks != NULL)
4290 struct elf_link_hash_entry *hlook;
4291 asection *slook;
4292 bfd_vma vlook;
4293 long ilook;
4294 size_t i, j, idx;
4296 hlook = weaks;
4297 weaks = hlook->u.weakdef;
4298 hlook->u.weakdef = NULL;
4300 BFD_ASSERT (hlook->root.type == bfd_link_hash_defined
4301 || hlook->root.type == bfd_link_hash_defweak
4302 || hlook->root.type == bfd_link_hash_common
4303 || hlook->root.type == bfd_link_hash_indirect);
4304 slook = hlook->root.u.def.section;
4305 vlook = hlook->root.u.def.value;
4307 ilook = -1;
4308 i = 0;
4309 j = sym_count;
4310 while (i < j)
4312 bfd_signed_vma vdiff;
4313 idx = (i + j) / 2;
4314 h = sorted_sym_hash [idx];
4315 vdiff = vlook - h->root.u.def.value;
4316 if (vdiff < 0)
4317 j = idx;
4318 else if (vdiff > 0)
4319 i = idx + 1;
4320 else
4322 long sdiff = slook->id - h->root.u.def.section->id;
4323 if (sdiff < 0)
4324 j = idx;
4325 else if (sdiff > 0)
4326 i = idx + 1;
4327 else
4329 ilook = idx;
4330 break;
4335 /* We didn't find a value/section match. */
4336 if (ilook == -1)
4337 continue;
4339 for (i = ilook; i < sym_count; i++)
4341 h = sorted_sym_hash [i];
4343 /* Stop if value or section doesn't match. */
4344 if (h->root.u.def.value != vlook
4345 || h->root.u.def.section != slook)
4346 break;
4347 else if (h != hlook)
4349 hlook->u.weakdef = h;
4351 /* If the weak definition is in the list of dynamic
4352 symbols, make sure the real definition is put
4353 there as well. */
4354 if (hlook->dynindx != -1 && h->dynindx == -1)
4356 if (! bfd_elf_link_record_dynamic_symbol (info, h))
4357 goto error_return;
4360 /* If the real definition is in the list of dynamic
4361 symbols, make sure the weak definition is put
4362 there as well. If we don't do this, then the
4363 dynamic loader might not merge the entries for the
4364 real definition and the weak definition. */
4365 if (h->dynindx != -1 && hlook->dynindx == -1)
4367 if (! bfd_elf_link_record_dynamic_symbol (info, hlook))
4368 goto error_return;
4370 break;
4375 free (sorted_sym_hash);
4378 if (bed->check_directives)
4379 (*bed->check_directives) (abfd, info);
4381 /* If this object is the same format as the output object, and it is
4382 not a shared library, then let the backend look through the
4383 relocs.
4385 This is required to build global offset table entries and to
4386 arrange for dynamic relocs. It is not required for the
4387 particular common case of linking non PIC code, even when linking
4388 against shared libraries, but unfortunately there is no way of
4389 knowing whether an object file has been compiled PIC or not.
4390 Looking through the relocs is not particularly time consuming.
4391 The problem is that we must either (1) keep the relocs in memory,
4392 which causes the linker to require additional runtime memory or
4393 (2) read the relocs twice from the input file, which wastes time.
4394 This would be a good case for using mmap.
4396 I have no idea how to handle linking PIC code into a file of a
4397 different format. It probably can't be done. */
4398 if (! dynamic
4399 && is_elf_hash_table (htab)
4400 && htab->root.creator == abfd->xvec
4401 && bed->check_relocs != NULL)
4403 asection *o;
4405 for (o = abfd->sections; o != NULL; o = o->next)
4407 Elf_Internal_Rela *internal_relocs;
4408 bfd_boolean ok;
4410 if ((o->flags & SEC_RELOC) == 0
4411 || o->reloc_count == 0
4412 || ((info->strip == strip_all || info->strip == strip_debugger)
4413 && (o->flags & SEC_DEBUGGING) != 0)
4414 || bfd_is_abs_section (o->output_section))
4415 continue;
4417 internal_relocs = _bfd_elf_link_read_relocs (abfd, o, NULL, NULL,
4418 info->keep_memory);
4419 if (internal_relocs == NULL)
4420 goto error_return;
4422 ok = (*bed->check_relocs) (abfd, info, o, internal_relocs);
4424 if (elf_section_data (o)->relocs != internal_relocs)
4425 free (internal_relocs);
4427 if (! ok)
4428 goto error_return;
4432 /* If this is a non-traditional link, try to optimize the handling
4433 of the .stab/.stabstr sections. */
4434 if (! dynamic
4435 && ! info->traditional_format
4436 && is_elf_hash_table (htab)
4437 && (info->strip != strip_all && info->strip != strip_debugger))
4439 asection *stabstr;
4441 stabstr = bfd_get_section_by_name (abfd, ".stabstr");
4442 if (stabstr != NULL)
4444 bfd_size_type string_offset = 0;
4445 asection *stab;
4447 for (stab = abfd->sections; stab; stab = stab->next)
4448 if (strncmp (".stab", stab->name, 5) == 0
4449 && (!stab->name[5] ||
4450 (stab->name[5] == '.' && ISDIGIT (stab->name[6])))
4451 && (stab->flags & SEC_MERGE) == 0
4452 && !bfd_is_abs_section (stab->output_section))
4454 struct bfd_elf_section_data *secdata;
4456 secdata = elf_section_data (stab);
4457 if (! _bfd_link_section_stabs (abfd, &htab->stab_info, stab,
4458 stabstr, &secdata->sec_info,
4459 &string_offset))
4460 goto error_return;
4461 if (secdata->sec_info)
4462 stab->sec_info_type = ELF_INFO_TYPE_STABS;
4467 if (is_elf_hash_table (htab) && add_needed)
4469 /* Add this bfd to the loaded list. */
4470 struct elf_link_loaded_list *n;
4472 n = bfd_alloc (abfd, sizeof (struct elf_link_loaded_list));
4473 if (n == NULL)
4474 goto error_return;
4475 n->abfd = abfd;
4476 n->next = htab->loaded;
4477 htab->loaded = n;
4480 return TRUE;
4482 error_free_vers:
4483 if (old_tab != NULL)
4484 free (old_tab);
4485 if (nondeflt_vers != NULL)
4486 free (nondeflt_vers);
4487 if (extversym != NULL)
4488 free (extversym);
4489 error_free_sym:
4490 if (isymbuf != NULL)
4491 free (isymbuf);
4492 error_return:
4493 return FALSE;
4496 /* Return the linker hash table entry of a symbol that might be
4497 satisfied by an archive symbol. Return -1 on error. */
4499 struct elf_link_hash_entry *
4500 _bfd_elf_archive_symbol_lookup (bfd *abfd,
4501 struct bfd_link_info *info,
4502 const char *name)
4504 struct elf_link_hash_entry *h;
4505 char *p, *copy;
4506 size_t len, first;
4508 h = elf_link_hash_lookup (elf_hash_table (info), name, FALSE, FALSE, FALSE);
4509 if (h != NULL)
4510 return h;
4512 /* If this is a default version (the name contains @@), look up the
4513 symbol again with only one `@' as well as without the version.
4514 The effect is that references to the symbol with and without the
4515 version will be matched by the default symbol in the archive. */
4517 p = strchr (name, ELF_VER_CHR);
4518 if (p == NULL || p[1] != ELF_VER_CHR)
4519 return h;
4521 /* First check with only one `@'. */
4522 len = strlen (name);
4523 copy = bfd_alloc (abfd, len);
4524 if (copy == NULL)
4525 return (struct elf_link_hash_entry *) 0 - 1;
4527 first = p - name + 1;
4528 memcpy (copy, name, first);
4529 memcpy (copy + first, name + first + 1, len - first);
4531 h = elf_link_hash_lookup (elf_hash_table (info), copy, FALSE, FALSE, FALSE);
4532 if (h == NULL)
4534 /* We also need to check references to the symbol without the
4535 version. */
4536 copy[first - 1] = '\0';
4537 h = elf_link_hash_lookup (elf_hash_table (info), copy,
4538 FALSE, FALSE, FALSE);
4541 bfd_release (abfd, copy);
4542 return h;
4545 /* Add symbols from an ELF archive file to the linker hash table. We
4546 don't use _bfd_generic_link_add_archive_symbols because of a
4547 problem which arises on UnixWare. The UnixWare libc.so is an
4548 archive which includes an entry libc.so.1 which defines a bunch of
4549 symbols. The libc.so archive also includes a number of other
4550 object files, which also define symbols, some of which are the same
4551 as those defined in libc.so.1. Correct linking requires that we
4552 consider each object file in turn, and include it if it defines any
4553 symbols we need. _bfd_generic_link_add_archive_symbols does not do
4554 this; it looks through the list of undefined symbols, and includes
4555 any object file which defines them. When this algorithm is used on
4556 UnixWare, it winds up pulling in libc.so.1 early and defining a
4557 bunch of symbols. This means that some of the other objects in the
4558 archive are not included in the link, which is incorrect since they
4559 precede libc.so.1 in the archive.
4561 Fortunately, ELF archive handling is simpler than that done by
4562 _bfd_generic_link_add_archive_symbols, which has to allow for a.out
4563 oddities. In ELF, if we find a symbol in the archive map, and the
4564 symbol is currently undefined, we know that we must pull in that
4565 object file.
4567 Unfortunately, we do have to make multiple passes over the symbol
4568 table until nothing further is resolved. */
4570 static bfd_boolean
4571 elf_link_add_archive_symbols (bfd *abfd, struct bfd_link_info *info)
4573 symindex c;
4574 bfd_boolean *defined = NULL;
4575 bfd_boolean *included = NULL;
4576 carsym *symdefs;
4577 bfd_boolean loop;
4578 bfd_size_type amt;
4579 const struct elf_backend_data *bed;
4580 struct elf_link_hash_entry * (*archive_symbol_lookup)
4581 (bfd *, struct bfd_link_info *, const char *);
4583 if (! bfd_has_map (abfd))
4585 /* An empty archive is a special case. */
4586 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
4587 return TRUE;
4588 bfd_set_error (bfd_error_no_armap);
4589 return FALSE;
4592 /* Keep track of all symbols we know to be already defined, and all
4593 files we know to be already included. This is to speed up the
4594 second and subsequent passes. */
4595 c = bfd_ardata (abfd)->symdef_count;
4596 if (c == 0)
4597 return TRUE;
4598 amt = c;
4599 amt *= sizeof (bfd_boolean);
4600 defined = bfd_zmalloc (amt);
4601 included = bfd_zmalloc (amt);
4602 if (defined == NULL || included == NULL)
4603 goto error_return;
4605 symdefs = bfd_ardata (abfd)->symdefs;
4606 bed = get_elf_backend_data (abfd);
4607 archive_symbol_lookup = bed->elf_backend_archive_symbol_lookup;
4611 file_ptr last;
4612 symindex i;
4613 carsym *symdef;
4614 carsym *symdefend;
4616 loop = FALSE;
4617 last = -1;
4619 symdef = symdefs;
4620 symdefend = symdef + c;
4621 for (i = 0; symdef < symdefend; symdef++, i++)
4623 struct elf_link_hash_entry *h;
4624 bfd *element;
4625 struct bfd_link_hash_entry *undefs_tail;
4626 symindex mark;
4628 if (defined[i] || included[i])
4629 continue;
4630 if (symdef->file_offset == last)
4632 included[i] = TRUE;
4633 continue;
4636 h = archive_symbol_lookup (abfd, info, symdef->name);
4637 if (h == (struct elf_link_hash_entry *) 0 - 1)
4638 goto error_return;
4640 if (h == NULL)
4641 continue;
4643 if (h->root.type == bfd_link_hash_common)
4645 /* We currently have a common symbol. The archive map contains
4646 a reference to this symbol, so we may want to include it. We
4647 only want to include it however, if this archive element
4648 contains a definition of the symbol, not just another common
4649 declaration of it.
4651 Unfortunately some archivers (including GNU ar) will put
4652 declarations of common symbols into their archive maps, as
4653 well as real definitions, so we cannot just go by the archive
4654 map alone. Instead we must read in the element's symbol
4655 table and check that to see what kind of symbol definition
4656 this is. */
4657 if (! elf_link_is_defined_archive_symbol (abfd, symdef))
4658 continue;
4660 else if (h->root.type != bfd_link_hash_undefined)
4662 if (h->root.type != bfd_link_hash_undefweak)
4663 defined[i] = TRUE;
4664 continue;
4667 /* We need to include this archive member. */
4668 element = _bfd_get_elt_at_filepos (abfd, symdef->file_offset);
4669 if (element == NULL)
4670 goto error_return;
4672 if (! bfd_check_format (element, bfd_object))
4673 goto error_return;
4675 /* Doublecheck that we have not included this object
4676 already--it should be impossible, but there may be
4677 something wrong with the archive. */
4678 if (element->archive_pass != 0)
4680 bfd_set_error (bfd_error_bad_value);
4681 goto error_return;
4683 element->archive_pass = 1;
4685 undefs_tail = info->hash->undefs_tail;
4687 if (! (*info->callbacks->add_archive_element) (info, element,
4688 symdef->name))
4689 goto error_return;
4690 if (! bfd_link_add_symbols (element, info))
4691 goto error_return;
4693 /* If there are any new undefined symbols, we need to make
4694 another pass through the archive in order to see whether
4695 they can be defined. FIXME: This isn't perfect, because
4696 common symbols wind up on undefs_tail and because an
4697 undefined symbol which is defined later on in this pass
4698 does not require another pass. This isn't a bug, but it
4699 does make the code less efficient than it could be. */
4700 if (undefs_tail != info->hash->undefs_tail)
4701 loop = TRUE;
4703 /* Look backward to mark all symbols from this object file
4704 which we have already seen in this pass. */
4705 mark = i;
4708 included[mark] = TRUE;
4709 if (mark == 0)
4710 break;
4711 --mark;
4713 while (symdefs[mark].file_offset == symdef->file_offset);
4715 /* We mark subsequent symbols from this object file as we go
4716 on through the loop. */
4717 last = symdef->file_offset;
4720 while (loop);
4722 free (defined);
4723 free (included);
4725 return TRUE;
4727 error_return:
4728 if (defined != NULL)
4729 free (defined);
4730 if (included != NULL)
4731 free (included);
4732 return FALSE;
4735 /* Given an ELF BFD, add symbols to the global hash table as
4736 appropriate. */
4738 bfd_boolean
4739 bfd_elf_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
4741 switch (bfd_get_format (abfd))
4743 case bfd_object:
4744 return elf_link_add_object_symbols (abfd, info);
4745 case bfd_archive:
4746 return elf_link_add_archive_symbols (abfd, info);
4747 default:
4748 bfd_set_error (bfd_error_wrong_format);
4749 return FALSE;
4753 /* This function will be called though elf_link_hash_traverse to store
4754 all hash value of the exported symbols in an array. */
4756 static bfd_boolean
4757 elf_collect_hash_codes (struct elf_link_hash_entry *h, void *data)
4759 unsigned long **valuep = data;
4760 const char *name;
4761 char *p;
4762 unsigned long ha;
4763 char *alc = NULL;
4765 if (h->root.type == bfd_link_hash_warning)
4766 h = (struct elf_link_hash_entry *) h->root.u.i.link;
4768 /* Ignore indirect symbols. These are added by the versioning code. */
4769 if (h->dynindx == -1)
4770 return TRUE;
4772 name = h->root.root.string;
4773 p = strchr (name, ELF_VER_CHR);
4774 if (p != NULL)
4776 alc = bfd_malloc (p - name + 1);
4777 memcpy (alc, name, p - name);
4778 alc[p - name] = '\0';
4779 name = alc;
4782 /* Compute the hash value. */
4783 ha = bfd_elf_hash (name);
4785 /* Store the found hash value in the array given as the argument. */
4786 *(*valuep)++ = ha;
4788 /* And store it in the struct so that we can put it in the hash table
4789 later. */
4790 h->u.elf_hash_value = ha;
4792 if (alc != NULL)
4793 free (alc);
4795 return TRUE;
4798 /* Array used to determine the number of hash table buckets to use
4799 based on the number of symbols there are. If there are fewer than
4800 3 symbols we use 1 bucket, fewer than 17 symbols we use 3 buckets,
4801 fewer than 37 we use 17 buckets, and so forth. We never use more
4802 than 32771 buckets. */
4804 static const size_t elf_buckets[] =
4806 1, 3, 17, 37, 67, 97, 131, 197, 263, 521, 1031, 2053, 4099, 8209,
4807 16411, 32771, 0
4810 /* Compute bucket count for hashing table. We do not use a static set
4811 of possible tables sizes anymore. Instead we determine for all
4812 possible reasonable sizes of the table the outcome (i.e., the
4813 number of collisions etc) and choose the best solution. The
4814 weighting functions are not too simple to allow the table to grow
4815 without bounds. Instead one of the weighting factors is the size.
4816 Therefore the result is always a good payoff between few collisions
4817 (= short chain lengths) and table size. */
4818 static size_t
4819 compute_bucket_count (struct bfd_link_info *info)
4821 size_t dynsymcount = elf_hash_table (info)->dynsymcount;
4822 size_t best_size = 0;
4823 unsigned long int *hashcodes;
4824 unsigned long int *hashcodesp;
4825 unsigned long int i;
4826 bfd_size_type amt;
4828 /* Compute the hash values for all exported symbols. At the same
4829 time store the values in an array so that we could use them for
4830 optimizations. */
4831 amt = dynsymcount;
4832 amt *= sizeof (unsigned long int);
4833 hashcodes = bfd_malloc (amt);
4834 if (hashcodes == NULL)
4835 return 0;
4836 hashcodesp = hashcodes;
4838 /* Put all hash values in HASHCODES. */
4839 elf_link_hash_traverse (elf_hash_table (info),
4840 elf_collect_hash_codes, &hashcodesp);
4842 /* We have a problem here. The following code to optimize the table
4843 size requires an integer type with more the 32 bits. If
4844 BFD_HOST_U_64_BIT is set we know about such a type. */
4845 #ifdef BFD_HOST_U_64_BIT
4846 if (info->optimize)
4848 unsigned long int nsyms = hashcodesp - hashcodes;
4849 size_t minsize;
4850 size_t maxsize;
4851 BFD_HOST_U_64_BIT best_chlen = ~((BFD_HOST_U_64_BIT) 0);
4852 unsigned long int *counts ;
4853 bfd *dynobj = elf_hash_table (info)->dynobj;
4854 const struct elf_backend_data *bed = get_elf_backend_data (dynobj);
4856 /* Possible optimization parameters: if we have NSYMS symbols we say
4857 that the hashing table must at least have NSYMS/4 and at most
4858 2*NSYMS buckets. */
4859 minsize = nsyms / 4;
4860 if (minsize == 0)
4861 minsize = 1;
4862 best_size = maxsize = nsyms * 2;
4864 /* Create array where we count the collisions in. We must use bfd_malloc
4865 since the size could be large. */
4866 amt = maxsize;
4867 amt *= sizeof (unsigned long int);
4868 counts = bfd_malloc (amt);
4869 if (counts == NULL)
4871 free (hashcodes);
4872 return 0;
4875 /* Compute the "optimal" size for the hash table. The criteria is a
4876 minimal chain length. The minor criteria is (of course) the size
4877 of the table. */
4878 for (i = minsize; i < maxsize; ++i)
4880 /* Walk through the array of hashcodes and count the collisions. */
4881 BFD_HOST_U_64_BIT max;
4882 unsigned long int j;
4883 unsigned long int fact;
4885 memset (counts, '\0', i * sizeof (unsigned long int));
4887 /* Determine how often each hash bucket is used. */
4888 for (j = 0; j < nsyms; ++j)
4889 ++counts[hashcodes[j] % i];
4891 /* For the weight function we need some information about the
4892 pagesize on the target. This is information need not be 100%
4893 accurate. Since this information is not available (so far) we
4894 define it here to a reasonable default value. If it is crucial
4895 to have a better value some day simply define this value. */
4896 # ifndef BFD_TARGET_PAGESIZE
4897 # define BFD_TARGET_PAGESIZE (4096)
4898 # endif
4900 /* We in any case need 2 + NSYMS entries for the size values and
4901 the chains. */
4902 max = (2 + nsyms) * (bed->s->arch_size / 8);
4904 # if 1
4905 /* Variant 1: optimize for short chains. We add the squares
4906 of all the chain lengths (which favors many small chain
4907 over a few long chains). */
4908 for (j = 0; j < i; ++j)
4909 max += counts[j] * counts[j];
4911 /* This adds penalties for the overall size of the table. */
4912 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4913 max *= fact * fact;
4914 # else
4915 /* Variant 2: Optimize a lot more for small table. Here we
4916 also add squares of the size but we also add penalties for
4917 empty slots (the +1 term). */
4918 for (j = 0; j < i; ++j)
4919 max += (1 + counts[j]) * (1 + counts[j]);
4921 /* The overall size of the table is considered, but not as
4922 strong as in variant 1, where it is squared. */
4923 fact = i / (BFD_TARGET_PAGESIZE / (bed->s->arch_size / 8)) + 1;
4924 max *= fact;
4925 # endif
4927 /* Compare with current best results. */
4928 if (max < best_chlen)
4930 best_chlen = max;
4931 best_size = i;
4935 free (counts);
4937 else
4938 #endif /* defined (BFD_HOST_U_64_BIT) */
4940 /* This is the fallback solution if no 64bit type is available or if we
4941 are not supposed to spend much time on optimizations. We select the
4942 bucket count using a fixed set of numbers. */
4943 for (i = 0; elf_buckets[i] != 0; i++)
4945 best_size = elf_buckets[i];
4946 if (dynsymcount < elf_buckets[i + 1])
4947 break;
4951 /* Free the arrays we needed. */
4952 free (hashcodes);
4954 return best_size;
4957 /* Set up the sizes and contents of the ELF dynamic sections. This is
4958 called by the ELF linker emulation before_allocation routine. We
4959 must set the sizes of the sections before the linker sets the
4960 addresses of the various sections. */
4962 bfd_boolean
4963 bfd_elf_size_dynamic_sections (bfd *output_bfd,
4964 const char *soname,
4965 const char *rpath,
4966 const char *filter_shlib,
4967 const char * const *auxiliary_filters,
4968 struct bfd_link_info *info,
4969 asection **sinterpptr,
4970 struct bfd_elf_version_tree *verdefs)
4972 bfd_size_type soname_indx;
4973 bfd *dynobj;
4974 const struct elf_backend_data *bed;
4975 struct elf_assign_sym_version_info asvinfo;
4977 *sinterpptr = NULL;
4979 soname_indx = (bfd_size_type) -1;
4981 if (!is_elf_hash_table (info->hash))
4982 return TRUE;
4984 elf_tdata (output_bfd)->relro = info->relro;
4985 if (info->execstack)
4986 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
4987 else if (info->noexecstack)
4988 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W;
4989 else
4991 bfd *inputobj;
4992 asection *notesec = NULL;
4993 int exec = 0;
4995 for (inputobj = info->input_bfds;
4996 inputobj;
4997 inputobj = inputobj->link_next)
4999 asection *s;
5001 if (inputobj->flags & (DYNAMIC | BFD_LINKER_CREATED))
5002 continue;
5003 s = bfd_get_section_by_name (inputobj, ".note.GNU-stack");
5004 if (s)
5006 if (s->flags & SEC_CODE)
5007 exec = PF_X;
5008 notesec = s;
5010 else
5011 exec = PF_X;
5013 if (notesec)
5015 elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | exec;
5016 if (exec && info->relocatable
5017 && notesec->output_section != bfd_abs_section_ptr)
5018 notesec->output_section->flags |= SEC_CODE;
5022 /* Any syms created from now on start with -1 in
5023 got.refcount/offset and plt.refcount/offset. */
5024 elf_hash_table (info)->init_got_refcount
5025 = elf_hash_table (info)->init_got_offset;
5026 elf_hash_table (info)->init_plt_refcount
5027 = elf_hash_table (info)->init_plt_offset;
5029 /* The backend may have to create some sections regardless of whether
5030 we're dynamic or not. */
5031 bed = get_elf_backend_data (output_bfd);
5032 if (bed->elf_backend_always_size_sections
5033 && ! (*bed->elf_backend_always_size_sections) (output_bfd, info))
5034 return FALSE;
5036 dynobj = elf_hash_table (info)->dynobj;
5038 /* If there were no dynamic objects in the link, there is nothing to
5039 do here. */
5040 if (dynobj == NULL)
5041 return TRUE;
5043 if (! _bfd_elf_maybe_strip_eh_frame_hdr (info))
5044 return FALSE;
5046 if (elf_hash_table (info)->dynamic_sections_created)
5048 struct elf_info_failed eif;
5049 struct elf_link_hash_entry *h;
5050 asection *dynstr;
5051 struct bfd_elf_version_tree *t;
5052 struct bfd_elf_version_expr *d;
5053 asection *s;
5054 bfd_boolean all_defined;
5056 *sinterpptr = bfd_get_section_by_name (dynobj, ".interp");
5057 BFD_ASSERT (*sinterpptr != NULL || !info->executable);
5059 if (soname != NULL)
5061 soname_indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5062 soname, TRUE);
5063 if (soname_indx == (bfd_size_type) -1
5064 || !_bfd_elf_add_dynamic_entry (info, DT_SONAME, soname_indx))
5065 return FALSE;
5068 if (info->symbolic)
5070 if (!_bfd_elf_add_dynamic_entry (info, DT_SYMBOLIC, 0))
5071 return FALSE;
5072 info->flags |= DF_SYMBOLIC;
5075 if (rpath != NULL)
5077 bfd_size_type indx;
5079 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr, rpath,
5080 TRUE);
5081 if (indx == (bfd_size_type) -1
5082 || !_bfd_elf_add_dynamic_entry (info, DT_RPATH, indx))
5083 return FALSE;
5085 if (info->new_dtags)
5087 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr, indx);
5088 if (!_bfd_elf_add_dynamic_entry (info, DT_RUNPATH, indx))
5089 return FALSE;
5093 if (filter_shlib != NULL)
5095 bfd_size_type indx;
5097 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5098 filter_shlib, TRUE);
5099 if (indx == (bfd_size_type) -1
5100 || !_bfd_elf_add_dynamic_entry (info, DT_FILTER, indx))
5101 return FALSE;
5104 if (auxiliary_filters != NULL)
5106 const char * const *p;
5108 for (p = auxiliary_filters; *p != NULL; p++)
5110 bfd_size_type indx;
5112 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5113 *p, TRUE);
5114 if (indx == (bfd_size_type) -1
5115 || !_bfd_elf_add_dynamic_entry (info, DT_AUXILIARY, indx))
5116 return FALSE;
5120 eif.info = info;
5121 eif.verdefs = verdefs;
5122 eif.failed = FALSE;
5124 /* If we are supposed to export all symbols into the dynamic symbol
5125 table (this is not the normal case), then do so. */
5126 if (info->export_dynamic)
5128 elf_link_hash_traverse (elf_hash_table (info),
5129 _bfd_elf_export_symbol,
5130 &eif);
5131 if (eif.failed)
5132 return FALSE;
5135 /* Make all global versions with definition. */
5136 for (t = verdefs; t != NULL; t = t->next)
5137 for (d = t->globals.list; d != NULL; d = d->next)
5138 if (!d->symver && d->symbol)
5140 const char *verstr, *name;
5141 size_t namelen, verlen, newlen;
5142 char *newname, *p;
5143 struct elf_link_hash_entry *newh;
5145 name = d->symbol;
5146 namelen = strlen (name);
5147 verstr = t->name;
5148 verlen = strlen (verstr);
5149 newlen = namelen + verlen + 3;
5151 newname = bfd_malloc (newlen);
5152 if (newname == NULL)
5153 return FALSE;
5154 memcpy (newname, name, namelen);
5156 /* Check the hidden versioned definition. */
5157 p = newname + namelen;
5158 *p++ = ELF_VER_CHR;
5159 memcpy (p, verstr, verlen + 1);
5160 newh = elf_link_hash_lookup (elf_hash_table (info),
5161 newname, FALSE, FALSE,
5162 FALSE);
5163 if (newh == NULL
5164 || (newh->root.type != bfd_link_hash_defined
5165 && newh->root.type != bfd_link_hash_defweak))
5167 /* Check the default versioned definition. */
5168 *p++ = ELF_VER_CHR;
5169 memcpy (p, verstr, verlen + 1);
5170 newh = elf_link_hash_lookup (elf_hash_table (info),
5171 newname, FALSE, FALSE,
5172 FALSE);
5174 free (newname);
5176 /* Mark this version if there is a definition and it is
5177 not defined in a shared object. */
5178 if (newh != NULL
5179 && !newh->def_dynamic
5180 && (newh->root.type == bfd_link_hash_defined
5181 || newh->root.type == bfd_link_hash_defweak))
5182 d->symver = 1;
5185 /* Attach all the symbols to their version information. */
5186 asvinfo.output_bfd = output_bfd;
5187 asvinfo.info = info;
5188 asvinfo.verdefs = verdefs;
5189 asvinfo.failed = FALSE;
5191 elf_link_hash_traverse (elf_hash_table (info),
5192 _bfd_elf_link_assign_sym_version,
5193 &asvinfo);
5194 if (asvinfo.failed)
5195 return FALSE;
5197 if (!info->allow_undefined_version)
5199 /* Check if all global versions have a definition. */
5200 all_defined = TRUE;
5201 for (t = verdefs; t != NULL; t = t->next)
5202 for (d = t->globals.list; d != NULL; d = d->next)
5203 if (!d->symver && !d->script)
5205 (*_bfd_error_handler)
5206 (_("%s: undefined version: %s"),
5207 d->pattern, t->name);
5208 all_defined = FALSE;
5211 if (!all_defined)
5213 bfd_set_error (bfd_error_bad_value);
5214 return FALSE;
5218 /* Find all symbols which were defined in a dynamic object and make
5219 the backend pick a reasonable value for them. */
5220 elf_link_hash_traverse (elf_hash_table (info),
5221 _bfd_elf_adjust_dynamic_symbol,
5222 &eif);
5223 if (eif.failed)
5224 return FALSE;
5226 /* Add some entries to the .dynamic section. We fill in some of the
5227 values later, in bfd_elf_final_link, but we must add the entries
5228 now so that we know the final size of the .dynamic section. */
5230 /* If there are initialization and/or finalization functions to
5231 call then add the corresponding DT_INIT/DT_FINI entries. */
5232 h = (info->init_function
5233 ? elf_link_hash_lookup (elf_hash_table (info),
5234 info->init_function, FALSE,
5235 FALSE, FALSE)
5236 : NULL);
5237 if (h != NULL
5238 && (h->ref_regular
5239 || h->def_regular))
5241 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT, 0))
5242 return FALSE;
5244 h = (info->fini_function
5245 ? elf_link_hash_lookup (elf_hash_table (info),
5246 info->fini_function, FALSE,
5247 FALSE, FALSE)
5248 : NULL);
5249 if (h != NULL
5250 && (h->ref_regular
5251 || h->def_regular))
5253 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI, 0))
5254 return FALSE;
5257 s = bfd_get_section_by_name (output_bfd, ".preinit_array");
5258 if (s != NULL && s->linker_has_input)
5260 /* DT_PREINIT_ARRAY is not allowed in shared library. */
5261 if (! info->executable)
5263 bfd *sub;
5264 asection *o;
5266 for (sub = info->input_bfds; sub != NULL;
5267 sub = sub->link_next)
5268 for (o = sub->sections; o != NULL; o = o->next)
5269 if (elf_section_data (o)->this_hdr.sh_type
5270 == SHT_PREINIT_ARRAY)
5272 (*_bfd_error_handler)
5273 (_("%B: .preinit_array section is not allowed in DSO"),
5274 sub);
5275 break;
5278 bfd_set_error (bfd_error_nonrepresentable_section);
5279 return FALSE;
5282 if (!_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAY, 0)
5283 || !_bfd_elf_add_dynamic_entry (info, DT_PREINIT_ARRAYSZ, 0))
5284 return FALSE;
5286 s = bfd_get_section_by_name (output_bfd, ".init_array");
5287 if (s != NULL && s->linker_has_input)
5289 if (!_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAY, 0)
5290 || !_bfd_elf_add_dynamic_entry (info, DT_INIT_ARRAYSZ, 0))
5291 return FALSE;
5293 s = bfd_get_section_by_name (output_bfd, ".fini_array");
5294 if (s != NULL && s->linker_has_input)
5296 if (!_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAY, 0)
5297 || !_bfd_elf_add_dynamic_entry (info, DT_FINI_ARRAYSZ, 0))
5298 return FALSE;
5301 dynstr = bfd_get_section_by_name (dynobj, ".dynstr");
5302 /* If .dynstr is excluded from the link, we don't want any of
5303 these tags. Strictly, we should be checking each section
5304 individually; This quick check covers for the case where
5305 someone does a /DISCARD/ : { *(*) }. */
5306 if (dynstr != NULL && dynstr->output_section != bfd_abs_section_ptr)
5308 bfd_size_type strsize;
5310 strsize = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5311 if (!_bfd_elf_add_dynamic_entry (info, DT_HASH, 0)
5312 || !_bfd_elf_add_dynamic_entry (info, DT_STRTAB, 0)
5313 || !_bfd_elf_add_dynamic_entry (info, DT_SYMTAB, 0)
5314 || !_bfd_elf_add_dynamic_entry (info, DT_STRSZ, strsize)
5315 || !_bfd_elf_add_dynamic_entry (info, DT_SYMENT,
5316 bed->s->sizeof_sym))
5317 return FALSE;
5321 /* The backend must work out the sizes of all the other dynamic
5322 sections. */
5323 if (bed->elf_backend_size_dynamic_sections
5324 && ! (*bed->elf_backend_size_dynamic_sections) (output_bfd, info))
5325 return FALSE;
5327 if (elf_hash_table (info)->dynamic_sections_created)
5329 unsigned long section_sym_count;
5330 asection *s;
5332 /* Set up the version definition section. */
5333 s = bfd_get_section_by_name (dynobj, ".gnu.version_d");
5334 BFD_ASSERT (s != NULL);
5336 /* We may have created additional version definitions if we are
5337 just linking a regular application. */
5338 verdefs = asvinfo.verdefs;
5340 /* Skip anonymous version tag. */
5341 if (verdefs != NULL && verdefs->vernum == 0)
5342 verdefs = verdefs->next;
5344 if (verdefs == NULL && !info->create_default_symver)
5345 s->flags |= SEC_EXCLUDE;
5346 else
5348 unsigned int cdefs;
5349 bfd_size_type size;
5350 struct bfd_elf_version_tree *t;
5351 bfd_byte *p;
5352 Elf_Internal_Verdef def;
5353 Elf_Internal_Verdaux defaux;
5354 struct bfd_link_hash_entry *bh;
5355 struct elf_link_hash_entry *h;
5356 const char *name;
5358 cdefs = 0;
5359 size = 0;
5361 /* Make space for the base version. */
5362 size += sizeof (Elf_External_Verdef);
5363 size += sizeof (Elf_External_Verdaux);
5364 ++cdefs;
5366 /* Make space for the default version. */
5367 if (info->create_default_symver)
5369 size += sizeof (Elf_External_Verdef);
5370 ++cdefs;
5373 for (t = verdefs; t != NULL; t = t->next)
5375 struct bfd_elf_version_deps *n;
5377 size += sizeof (Elf_External_Verdef);
5378 size += sizeof (Elf_External_Verdaux);
5379 ++cdefs;
5381 for (n = t->deps; n != NULL; n = n->next)
5382 size += sizeof (Elf_External_Verdaux);
5385 s->size = size;
5386 s->contents = bfd_alloc (output_bfd, s->size);
5387 if (s->contents == NULL && s->size != 0)
5388 return FALSE;
5390 /* Fill in the version definition section. */
5392 p = s->contents;
5394 def.vd_version = VER_DEF_CURRENT;
5395 def.vd_flags = VER_FLG_BASE;
5396 def.vd_ndx = 1;
5397 def.vd_cnt = 1;
5398 if (info->create_default_symver)
5400 def.vd_aux = 2 * sizeof (Elf_External_Verdef);
5401 def.vd_next = sizeof (Elf_External_Verdef);
5403 else
5405 def.vd_aux = sizeof (Elf_External_Verdef);
5406 def.vd_next = (sizeof (Elf_External_Verdef)
5407 + sizeof (Elf_External_Verdaux));
5410 if (soname_indx != (bfd_size_type) -1)
5412 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5413 soname_indx);
5414 def.vd_hash = bfd_elf_hash (soname);
5415 defaux.vda_name = soname_indx;
5416 name = soname;
5418 else
5420 bfd_size_type indx;
5422 name = lbasename (output_bfd->filename);
5423 def.vd_hash = bfd_elf_hash (name);
5424 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5425 name, FALSE);
5426 if (indx == (bfd_size_type) -1)
5427 return FALSE;
5428 defaux.vda_name = indx;
5430 defaux.vda_next = 0;
5432 _bfd_elf_swap_verdef_out (output_bfd, &def,
5433 (Elf_External_Verdef *) p);
5434 p += sizeof (Elf_External_Verdef);
5435 if (info->create_default_symver)
5437 /* Add a symbol representing this version. */
5438 bh = NULL;
5439 if (! (_bfd_generic_link_add_one_symbol
5440 (info, dynobj, name, BSF_GLOBAL, bfd_abs_section_ptr,
5441 0, NULL, FALSE,
5442 get_elf_backend_data (dynobj)->collect, &bh)))
5443 return FALSE;
5444 h = (struct elf_link_hash_entry *) bh;
5445 h->non_elf = 0;
5446 h->def_regular = 1;
5447 h->type = STT_OBJECT;
5448 h->verinfo.vertree = NULL;
5450 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5451 return FALSE;
5453 /* Create a duplicate of the base version with the same
5454 aux block, but different flags. */
5455 def.vd_flags = 0;
5456 def.vd_ndx = 2;
5457 def.vd_aux = sizeof (Elf_External_Verdef);
5458 if (verdefs)
5459 def.vd_next = (sizeof (Elf_External_Verdef)
5460 + sizeof (Elf_External_Verdaux));
5461 else
5462 def.vd_next = 0;
5463 _bfd_elf_swap_verdef_out (output_bfd, &def,
5464 (Elf_External_Verdef *) p);
5465 p += sizeof (Elf_External_Verdef);
5467 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5468 (Elf_External_Verdaux *) p);
5469 p += sizeof (Elf_External_Verdaux);
5471 for (t = verdefs; t != NULL; t = t->next)
5473 unsigned int cdeps;
5474 struct bfd_elf_version_deps *n;
5476 cdeps = 0;
5477 for (n = t->deps; n != NULL; n = n->next)
5478 ++cdeps;
5480 /* Add a symbol representing this version. */
5481 bh = NULL;
5482 if (! (_bfd_generic_link_add_one_symbol
5483 (info, dynobj, t->name, BSF_GLOBAL, bfd_abs_section_ptr,
5484 0, NULL, FALSE,
5485 get_elf_backend_data (dynobj)->collect, &bh)))
5486 return FALSE;
5487 h = (struct elf_link_hash_entry *) bh;
5488 h->non_elf = 0;
5489 h->def_regular = 1;
5490 h->type = STT_OBJECT;
5491 h->verinfo.vertree = t;
5493 if (! bfd_elf_link_record_dynamic_symbol (info, h))
5494 return FALSE;
5496 def.vd_version = VER_DEF_CURRENT;
5497 def.vd_flags = 0;
5498 if (t->globals.list == NULL
5499 && t->locals.list == NULL
5500 && ! t->used)
5501 def.vd_flags |= VER_FLG_WEAK;
5502 def.vd_ndx = t->vernum + (info->create_default_symver ? 2 : 1);
5503 def.vd_cnt = cdeps + 1;
5504 def.vd_hash = bfd_elf_hash (t->name);
5505 def.vd_aux = sizeof (Elf_External_Verdef);
5506 def.vd_next = 0;
5507 if (t->next != NULL)
5508 def.vd_next = (sizeof (Elf_External_Verdef)
5509 + (cdeps + 1) * sizeof (Elf_External_Verdaux));
5511 _bfd_elf_swap_verdef_out (output_bfd, &def,
5512 (Elf_External_Verdef *) p);
5513 p += sizeof (Elf_External_Verdef);
5515 defaux.vda_name = h->dynstr_index;
5516 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5517 h->dynstr_index);
5518 defaux.vda_next = 0;
5519 if (t->deps != NULL)
5520 defaux.vda_next = sizeof (Elf_External_Verdaux);
5521 t->name_indx = defaux.vda_name;
5523 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5524 (Elf_External_Verdaux *) p);
5525 p += sizeof (Elf_External_Verdaux);
5527 for (n = t->deps; n != NULL; n = n->next)
5529 if (n->version_needed == NULL)
5531 /* This can happen if there was an error in the
5532 version script. */
5533 defaux.vda_name = 0;
5535 else
5537 defaux.vda_name = n->version_needed->name_indx;
5538 _bfd_elf_strtab_addref (elf_hash_table (info)->dynstr,
5539 defaux.vda_name);
5541 if (n->next == NULL)
5542 defaux.vda_next = 0;
5543 else
5544 defaux.vda_next = sizeof (Elf_External_Verdaux);
5546 _bfd_elf_swap_verdaux_out (output_bfd, &defaux,
5547 (Elf_External_Verdaux *) p);
5548 p += sizeof (Elf_External_Verdaux);
5552 if (!_bfd_elf_add_dynamic_entry (info, DT_VERDEF, 0)
5553 || !_bfd_elf_add_dynamic_entry (info, DT_VERDEFNUM, cdefs))
5554 return FALSE;
5556 elf_tdata (output_bfd)->cverdefs = cdefs;
5559 if ((info->new_dtags && info->flags) || (info->flags & DF_STATIC_TLS))
5561 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS, info->flags))
5562 return FALSE;
5564 else if (info->flags & DF_BIND_NOW)
5566 if (!_bfd_elf_add_dynamic_entry (info, DT_BIND_NOW, 0))
5567 return FALSE;
5570 if (info->flags_1)
5572 if (info->executable)
5573 info->flags_1 &= ~ (DF_1_INITFIRST
5574 | DF_1_NODELETE
5575 | DF_1_NOOPEN);
5576 if (!_bfd_elf_add_dynamic_entry (info, DT_FLAGS_1, info->flags_1))
5577 return FALSE;
5580 /* Work out the size of the version reference section. */
5582 s = bfd_get_section_by_name (dynobj, ".gnu.version_r");
5583 BFD_ASSERT (s != NULL);
5585 struct elf_find_verdep_info sinfo;
5587 sinfo.output_bfd = output_bfd;
5588 sinfo.info = info;
5589 sinfo.vers = elf_tdata (output_bfd)->cverdefs;
5590 if (sinfo.vers == 0)
5591 sinfo.vers = 1;
5592 sinfo.failed = FALSE;
5594 elf_link_hash_traverse (elf_hash_table (info),
5595 _bfd_elf_link_find_version_dependencies,
5596 &sinfo);
5598 if (elf_tdata (output_bfd)->verref == NULL)
5599 s->flags |= SEC_EXCLUDE;
5600 else
5602 Elf_Internal_Verneed *t;
5603 unsigned int size;
5604 unsigned int crefs;
5605 bfd_byte *p;
5607 /* Build the version definition section. */
5608 size = 0;
5609 crefs = 0;
5610 for (t = elf_tdata (output_bfd)->verref;
5611 t != NULL;
5612 t = t->vn_nextref)
5614 Elf_Internal_Vernaux *a;
5616 size += sizeof (Elf_External_Verneed);
5617 ++crefs;
5618 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5619 size += sizeof (Elf_External_Vernaux);
5622 s->size = size;
5623 s->contents = bfd_alloc (output_bfd, s->size);
5624 if (s->contents == NULL)
5625 return FALSE;
5627 p = s->contents;
5628 for (t = elf_tdata (output_bfd)->verref;
5629 t != NULL;
5630 t = t->vn_nextref)
5632 unsigned int caux;
5633 Elf_Internal_Vernaux *a;
5634 bfd_size_type indx;
5636 caux = 0;
5637 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5638 ++caux;
5640 t->vn_version = VER_NEED_CURRENT;
5641 t->vn_cnt = caux;
5642 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5643 elf_dt_name (t->vn_bfd) != NULL
5644 ? elf_dt_name (t->vn_bfd)
5645 : lbasename (t->vn_bfd->filename),
5646 FALSE);
5647 if (indx == (bfd_size_type) -1)
5648 return FALSE;
5649 t->vn_file = indx;
5650 t->vn_aux = sizeof (Elf_External_Verneed);
5651 if (t->vn_nextref == NULL)
5652 t->vn_next = 0;
5653 else
5654 t->vn_next = (sizeof (Elf_External_Verneed)
5655 + caux * sizeof (Elf_External_Vernaux));
5657 _bfd_elf_swap_verneed_out (output_bfd, t,
5658 (Elf_External_Verneed *) p);
5659 p += sizeof (Elf_External_Verneed);
5661 for (a = t->vn_auxptr; a != NULL; a = a->vna_nextptr)
5663 a->vna_hash = bfd_elf_hash (a->vna_nodename);
5664 indx = _bfd_elf_strtab_add (elf_hash_table (info)->dynstr,
5665 a->vna_nodename, FALSE);
5666 if (indx == (bfd_size_type) -1)
5667 return FALSE;
5668 a->vna_name = indx;
5669 if (a->vna_nextptr == NULL)
5670 a->vna_next = 0;
5671 else
5672 a->vna_next = sizeof (Elf_External_Vernaux);
5674 _bfd_elf_swap_vernaux_out (output_bfd, a,
5675 (Elf_External_Vernaux *) p);
5676 p += sizeof (Elf_External_Vernaux);
5680 if (!_bfd_elf_add_dynamic_entry (info, DT_VERNEED, 0)
5681 || !_bfd_elf_add_dynamic_entry (info, DT_VERNEEDNUM, crefs))
5682 return FALSE;
5684 elf_tdata (output_bfd)->cverrefs = crefs;
5688 if ((elf_tdata (output_bfd)->cverrefs == 0
5689 && elf_tdata (output_bfd)->cverdefs == 0)
5690 || _bfd_elf_link_renumber_dynsyms (output_bfd, info,
5691 &section_sym_count) == 0)
5693 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5694 s->flags |= SEC_EXCLUDE;
5697 return TRUE;
5700 bfd_boolean
5701 bfd_elf_size_dynsym_hash_dynstr (bfd *output_bfd, struct bfd_link_info *info)
5703 if (!is_elf_hash_table (info->hash))
5704 return TRUE;
5706 if (elf_hash_table (info)->dynamic_sections_created)
5708 bfd *dynobj;
5709 const struct elf_backend_data *bed;
5710 asection *s;
5711 bfd_size_type dynsymcount;
5712 unsigned long section_sym_count;
5713 size_t bucketcount = 0;
5714 size_t hash_entry_size;
5715 unsigned int dtagcount;
5717 dynobj = elf_hash_table (info)->dynobj;
5719 /* Assign dynsym indicies. In a shared library we generate a
5720 section symbol for each output section, which come first.
5721 Next come all of the back-end allocated local dynamic syms,
5722 followed by the rest of the global symbols. */
5724 dynsymcount = _bfd_elf_link_renumber_dynsyms (output_bfd, info,
5725 &section_sym_count);
5727 /* Work out the size of the symbol version section. */
5728 s = bfd_get_section_by_name (dynobj, ".gnu.version");
5729 BFD_ASSERT (s != NULL);
5730 if (dynsymcount != 0
5731 && (s->flags & SEC_EXCLUDE) == 0)
5733 s->size = dynsymcount * sizeof (Elf_External_Versym);
5734 s->contents = bfd_zalloc (output_bfd, s->size);
5735 if (s->contents == NULL)
5736 return FALSE;
5738 if (!_bfd_elf_add_dynamic_entry (info, DT_VERSYM, 0))
5739 return FALSE;
5742 /* Set the size of the .dynsym and .hash sections. We counted
5743 the number of dynamic symbols in elf_link_add_object_symbols.
5744 We will build the contents of .dynsym and .hash when we build
5745 the final symbol table, because until then we do not know the
5746 correct value to give the symbols. We built the .dynstr
5747 section as we went along in elf_link_add_object_symbols. */
5748 s = bfd_get_section_by_name (dynobj, ".dynsym");
5749 BFD_ASSERT (s != NULL);
5750 bed = get_elf_backend_data (output_bfd);
5751 s->size = dynsymcount * bed->s->sizeof_sym;
5753 if (dynsymcount != 0)
5755 s->contents = bfd_alloc (output_bfd, s->size);
5756 if (s->contents == NULL)
5757 return FALSE;
5759 /* The first entry in .dynsym is a dummy symbol.
5760 Clear all the section syms, in case we don't output them all. */
5761 ++section_sym_count;
5762 memset (s->contents, 0, section_sym_count * bed->s->sizeof_sym);
5765 /* Compute the size of the hashing table. As a side effect this
5766 computes the hash values for all the names we export. */
5767 bucketcount = compute_bucket_count (info);
5769 s = bfd_get_section_by_name (dynobj, ".hash");
5770 BFD_ASSERT (s != NULL);
5771 hash_entry_size = elf_section_data (s)->this_hdr.sh_entsize;
5772 s->size = ((2 + bucketcount + dynsymcount) * hash_entry_size);
5773 s->contents = bfd_zalloc (output_bfd, s->size);
5774 if (s->contents == NULL)
5775 return FALSE;
5777 bfd_put (8 * hash_entry_size, output_bfd, bucketcount, s->contents);
5778 bfd_put (8 * hash_entry_size, output_bfd, dynsymcount,
5779 s->contents + hash_entry_size);
5781 elf_hash_table (info)->bucketcount = bucketcount;
5783 s = bfd_get_section_by_name (dynobj, ".dynstr");
5784 BFD_ASSERT (s != NULL);
5786 elf_finalize_dynstr (output_bfd, info);
5788 s->size = _bfd_elf_strtab_size (elf_hash_table (info)->dynstr);
5790 for (dtagcount = 0; dtagcount <= info->spare_dynamic_tags; ++dtagcount)
5791 if (!_bfd_elf_add_dynamic_entry (info, DT_NULL, 0))
5792 return FALSE;
5795 return TRUE;
5798 /* Final phase of ELF linker. */
5800 /* A structure we use to avoid passing large numbers of arguments. */
5802 struct elf_final_link_info
5804 /* General link information. */
5805 struct bfd_link_info *info;
5806 /* Output BFD. */
5807 bfd *output_bfd;
5808 /* Symbol string table. */
5809 struct bfd_strtab_hash *symstrtab;
5810 /* .dynsym section. */
5811 asection *dynsym_sec;
5812 /* .hash section. */
5813 asection *hash_sec;
5814 /* symbol version section (.gnu.version). */
5815 asection *symver_sec;
5816 /* Buffer large enough to hold contents of any section. */
5817 bfd_byte *contents;
5818 /* Buffer large enough to hold external relocs of any section. */
5819 void *external_relocs;
5820 /* Buffer large enough to hold internal relocs of any section. */
5821 Elf_Internal_Rela *internal_relocs;
5822 /* Buffer large enough to hold external local symbols of any input
5823 BFD. */
5824 bfd_byte *external_syms;
5825 /* And a buffer for symbol section indices. */
5826 Elf_External_Sym_Shndx *locsym_shndx;
5827 /* Buffer large enough to hold internal local symbols of any input
5828 BFD. */
5829 Elf_Internal_Sym *internal_syms;
5830 /* Array large enough to hold a symbol index for each local symbol
5831 of any input BFD. */
5832 long *indices;
5833 /* Array large enough to hold a section pointer for each local
5834 symbol of any input BFD. */
5835 asection **sections;
5836 /* Buffer to hold swapped out symbols. */
5837 bfd_byte *symbuf;
5838 /* And one for symbol section indices. */
5839 Elf_External_Sym_Shndx *symshndxbuf;
5840 /* Number of swapped out symbols in buffer. */
5841 size_t symbuf_count;
5842 /* Number of symbols which fit in symbuf. */
5843 size_t symbuf_size;
5844 /* And same for symshndxbuf. */
5845 size_t shndxbuf_size;
5848 /* This struct is used to pass information to elf_link_output_extsym. */
5850 struct elf_outext_info
5852 bfd_boolean failed;
5853 bfd_boolean localsyms;
5854 struct elf_final_link_info *finfo;
5857 /* When performing a relocatable link, the input relocations are
5858 preserved. But, if they reference global symbols, the indices
5859 referenced must be updated. Update all the relocations in
5860 REL_HDR (there are COUNT of them), using the data in REL_HASH. */
5862 static void
5863 elf_link_adjust_relocs (bfd *abfd,
5864 Elf_Internal_Shdr *rel_hdr,
5865 unsigned int count,
5866 struct elf_link_hash_entry **rel_hash)
5868 unsigned int i;
5869 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5870 bfd_byte *erela;
5871 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5872 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5873 bfd_vma r_type_mask;
5874 int r_sym_shift;
5876 if (rel_hdr->sh_entsize == bed->s->sizeof_rel)
5878 swap_in = bed->s->swap_reloc_in;
5879 swap_out = bed->s->swap_reloc_out;
5881 else if (rel_hdr->sh_entsize == bed->s->sizeof_rela)
5883 swap_in = bed->s->swap_reloca_in;
5884 swap_out = bed->s->swap_reloca_out;
5886 else
5887 abort ();
5889 if (bed->s->int_rels_per_ext_rel > MAX_INT_RELS_PER_EXT_REL)
5890 abort ();
5892 if (bed->s->arch_size == 32)
5894 r_type_mask = 0xff;
5895 r_sym_shift = 8;
5897 else
5899 r_type_mask = 0xffffffff;
5900 r_sym_shift = 32;
5903 erela = rel_hdr->contents;
5904 for (i = 0; i < count; i++, rel_hash++, erela += rel_hdr->sh_entsize)
5906 Elf_Internal_Rela irela[MAX_INT_RELS_PER_EXT_REL];
5907 unsigned int j;
5909 if (*rel_hash == NULL)
5910 continue;
5912 BFD_ASSERT ((*rel_hash)->indx >= 0);
5914 (*swap_in) (abfd, erela, irela);
5915 for (j = 0; j < bed->s->int_rels_per_ext_rel; j++)
5916 irela[j].r_info = ((bfd_vma) (*rel_hash)->indx << r_sym_shift
5917 | (irela[j].r_info & r_type_mask));
5918 (*swap_out) (abfd, irela, erela);
5922 struct elf_link_sort_rela
5924 union {
5925 bfd_vma offset;
5926 bfd_vma sym_mask;
5927 } u;
5928 enum elf_reloc_type_class type;
5929 /* We use this as an array of size int_rels_per_ext_rel. */
5930 Elf_Internal_Rela rela[1];
5933 static int
5934 elf_link_sort_cmp1 (const void *A, const void *B)
5936 const struct elf_link_sort_rela *a = A;
5937 const struct elf_link_sort_rela *b = B;
5938 int relativea, relativeb;
5940 relativea = a->type == reloc_class_relative;
5941 relativeb = b->type == reloc_class_relative;
5943 if (relativea < relativeb)
5944 return 1;
5945 if (relativea > relativeb)
5946 return -1;
5947 if ((a->rela->r_info & a->u.sym_mask) < (b->rela->r_info & b->u.sym_mask))
5948 return -1;
5949 if ((a->rela->r_info & a->u.sym_mask) > (b->rela->r_info & b->u.sym_mask))
5950 return 1;
5951 if (a->rela->r_offset < b->rela->r_offset)
5952 return -1;
5953 if (a->rela->r_offset > b->rela->r_offset)
5954 return 1;
5955 return 0;
5958 static int
5959 elf_link_sort_cmp2 (const void *A, const void *B)
5961 const struct elf_link_sort_rela *a = A;
5962 const struct elf_link_sort_rela *b = B;
5963 int copya, copyb;
5965 if (a->u.offset < b->u.offset)
5966 return -1;
5967 if (a->u.offset > b->u.offset)
5968 return 1;
5969 copya = (a->type == reloc_class_copy) * 2 + (a->type == reloc_class_plt);
5970 copyb = (b->type == reloc_class_copy) * 2 + (b->type == reloc_class_plt);
5971 if (copya < copyb)
5972 return -1;
5973 if (copya > copyb)
5974 return 1;
5975 if (a->rela->r_offset < b->rela->r_offset)
5976 return -1;
5977 if (a->rela->r_offset > b->rela->r_offset)
5978 return 1;
5979 return 0;
5982 static size_t
5983 elf_link_sort_relocs (bfd *abfd, struct bfd_link_info *info, asection **psec)
5985 asection *reldyn;
5986 bfd_size_type count, size;
5987 size_t i, ret, sort_elt, ext_size;
5988 bfd_byte *sort, *s_non_relative, *p;
5989 struct elf_link_sort_rela *sq;
5990 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
5991 int i2e = bed->s->int_rels_per_ext_rel;
5992 void (*swap_in) (bfd *, const bfd_byte *, Elf_Internal_Rela *);
5993 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
5994 struct bfd_link_order *lo;
5995 bfd_vma r_sym_mask;
5997 reldyn = bfd_get_section_by_name (abfd, ".rela.dyn");
5998 if (reldyn == NULL || reldyn->size == 0)
6000 reldyn = bfd_get_section_by_name (abfd, ".rel.dyn");
6001 if (reldyn == NULL || reldyn->size == 0)
6002 return 0;
6003 ext_size = bed->s->sizeof_rel;
6004 swap_in = bed->s->swap_reloc_in;
6005 swap_out = bed->s->swap_reloc_out;
6007 else
6009 ext_size = bed->s->sizeof_rela;
6010 swap_in = bed->s->swap_reloca_in;
6011 swap_out = bed->s->swap_reloca_out;
6013 count = reldyn->size / ext_size;
6015 size = 0;
6016 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6017 if (lo->type == bfd_indirect_link_order)
6019 asection *o = lo->u.indirect.section;
6020 size += o->size;
6023 if (size != reldyn->size)
6024 return 0;
6026 sort_elt = (sizeof (struct elf_link_sort_rela)
6027 + (i2e - 1) * sizeof (Elf_Internal_Rela));
6028 sort = bfd_zmalloc (sort_elt * count);
6029 if (sort == NULL)
6031 (*info->callbacks->warning)
6032 (info, _("Not enough memory to sort relocations"), 0, abfd, 0, 0);
6033 return 0;
6036 if (bed->s->arch_size == 32)
6037 r_sym_mask = ~(bfd_vma) 0xff;
6038 else
6039 r_sym_mask = ~(bfd_vma) 0xffffffff;
6041 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6042 if (lo->type == bfd_indirect_link_order)
6044 bfd_byte *erel, *erelend;
6045 asection *o = lo->u.indirect.section;
6047 if (o->contents == NULL && o->size != 0)
6049 /* This is a reloc section that is being handled as a normal
6050 section. See bfd_section_from_shdr. We can't combine
6051 relocs in this case. */
6052 free (sort);
6053 return 0;
6055 erel = o->contents;
6056 erelend = o->contents + o->size;
6057 p = sort + o->output_offset / ext_size * sort_elt;
6058 while (erel < erelend)
6060 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6061 (*swap_in) (abfd, erel, s->rela);
6062 s->type = (*bed->elf_backend_reloc_type_class) (s->rela);
6063 s->u.sym_mask = r_sym_mask;
6064 p += sort_elt;
6065 erel += ext_size;
6069 qsort (sort, count, sort_elt, elf_link_sort_cmp1);
6071 for (i = 0, p = sort; i < count; i++, p += sort_elt)
6073 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6074 if (s->type != reloc_class_relative)
6075 break;
6077 ret = i;
6078 s_non_relative = p;
6080 sq = (struct elf_link_sort_rela *) s_non_relative;
6081 for (; i < count; i++, p += sort_elt)
6083 struct elf_link_sort_rela *sp = (struct elf_link_sort_rela *) p;
6084 if (((sp->rela->r_info ^ sq->rela->r_info) & r_sym_mask) != 0)
6085 sq = sp;
6086 sp->u.offset = sq->rela->r_offset;
6089 qsort (s_non_relative, count - ret, sort_elt, elf_link_sort_cmp2);
6091 for (lo = reldyn->map_head.link_order; lo != NULL; lo = lo->next)
6092 if (lo->type == bfd_indirect_link_order)
6094 bfd_byte *erel, *erelend;
6095 asection *o = lo->u.indirect.section;
6097 erel = o->contents;
6098 erelend = o->contents + o->size;
6099 p = sort + o->output_offset / ext_size * sort_elt;
6100 while (erel < erelend)
6102 struct elf_link_sort_rela *s = (struct elf_link_sort_rela *) p;
6103 (*swap_out) (abfd, s->rela, erel);
6104 p += sort_elt;
6105 erel += ext_size;
6109 free (sort);
6110 *psec = reldyn;
6111 return ret;
6114 /* Flush the output symbols to the file. */
6116 static bfd_boolean
6117 elf_link_flush_output_syms (struct elf_final_link_info *finfo,
6118 const struct elf_backend_data *bed)
6120 if (finfo->symbuf_count > 0)
6122 Elf_Internal_Shdr *hdr;
6123 file_ptr pos;
6124 bfd_size_type amt;
6126 hdr = &elf_tdata (finfo->output_bfd)->symtab_hdr;
6127 pos = hdr->sh_offset + hdr->sh_size;
6128 amt = finfo->symbuf_count * bed->s->sizeof_sym;
6129 if (bfd_seek (finfo->output_bfd, pos, SEEK_SET) != 0
6130 || bfd_bwrite (finfo->symbuf, amt, finfo->output_bfd) != amt)
6131 return FALSE;
6133 hdr->sh_size += amt;
6134 finfo->symbuf_count = 0;
6137 return TRUE;
6140 /* Add a symbol to the output symbol table. */
6142 static bfd_boolean
6143 elf_link_output_sym (struct elf_final_link_info *finfo,
6144 const char *name,
6145 Elf_Internal_Sym *elfsym,
6146 asection *input_sec,
6147 struct elf_link_hash_entry *h)
6149 bfd_byte *dest;
6150 Elf_External_Sym_Shndx *destshndx;
6151 bfd_boolean (*output_symbol_hook)
6152 (struct bfd_link_info *, const char *, Elf_Internal_Sym *, asection *,
6153 struct elf_link_hash_entry *);
6154 const struct elf_backend_data *bed;
6156 bed = get_elf_backend_data (finfo->output_bfd);
6157 output_symbol_hook = bed->elf_backend_link_output_symbol_hook;
6158 if (output_symbol_hook != NULL)
6160 if (! (*output_symbol_hook) (finfo->info, name, elfsym, input_sec, h))
6161 return FALSE;
6164 if (name == NULL || *name == '\0')
6165 elfsym->st_name = 0;
6166 else if (input_sec->flags & SEC_EXCLUDE)
6167 elfsym->st_name = 0;
6168 else
6170 elfsym->st_name = (unsigned long) _bfd_stringtab_add (finfo->symstrtab,
6171 name, TRUE, FALSE);
6172 if (elfsym->st_name == (unsigned long) -1)
6173 return FALSE;
6176 if (finfo->symbuf_count >= finfo->symbuf_size)
6178 if (! elf_link_flush_output_syms (finfo, bed))
6179 return FALSE;
6182 dest = finfo->symbuf + finfo->symbuf_count * bed->s->sizeof_sym;
6183 destshndx = finfo->symshndxbuf;
6184 if (destshndx != NULL)
6186 if (bfd_get_symcount (finfo->output_bfd) >= finfo->shndxbuf_size)
6188 bfd_size_type amt;
6190 amt = finfo->shndxbuf_size * sizeof (Elf_External_Sym_Shndx);
6191 finfo->symshndxbuf = destshndx = bfd_realloc (destshndx, amt * 2);
6192 if (destshndx == NULL)
6193 return FALSE;
6194 memset ((char *) destshndx + amt, 0, amt);
6195 finfo->shndxbuf_size *= 2;
6197 destshndx += bfd_get_symcount (finfo->output_bfd);
6200 bed->s->swap_symbol_out (finfo->output_bfd, elfsym, dest, destshndx);
6201 finfo->symbuf_count += 1;
6202 bfd_get_symcount (finfo->output_bfd) += 1;
6204 return TRUE;
6207 /* Return TRUE if the dynamic symbol SYM in ABFD is supported. */
6209 static bfd_boolean
6210 check_dynsym (bfd *abfd, Elf_Internal_Sym *sym)
6212 if (sym->st_shndx > SHN_HIRESERVE)
6214 /* The gABI doesn't support dynamic symbols in output sections
6215 beyond 64k. */
6216 (*_bfd_error_handler)
6217 (_("%B: Too many sections: %d (>= %d)"),
6218 abfd, bfd_count_sections (abfd), SHN_LORESERVE);
6219 bfd_set_error (bfd_error_nonrepresentable_section);
6220 return FALSE;
6222 return TRUE;
6225 /* For DSOs loaded in via a DT_NEEDED entry, emulate ld.so in
6226 allowing an unsatisfied unversioned symbol in the DSO to match a
6227 versioned symbol that would normally require an explicit version.
6228 We also handle the case that a DSO references a hidden symbol
6229 which may be satisfied by a versioned symbol in another DSO. */
6231 static bfd_boolean
6232 elf_link_check_versioned_symbol (struct bfd_link_info *info,
6233 const struct elf_backend_data *bed,
6234 struct elf_link_hash_entry *h)
6236 bfd *abfd;
6237 struct elf_link_loaded_list *loaded;
6239 if (!is_elf_hash_table (info->hash))
6240 return FALSE;
6242 switch (h->root.type)
6244 default:
6245 abfd = NULL;
6246 break;
6248 case bfd_link_hash_undefined:
6249 case bfd_link_hash_undefweak:
6250 abfd = h->root.u.undef.abfd;
6251 if ((abfd->flags & DYNAMIC) == 0
6252 || (elf_dyn_lib_class (abfd) & DYN_DT_NEEDED) == 0)
6253 return FALSE;
6254 break;
6256 case bfd_link_hash_defined:
6257 case bfd_link_hash_defweak:
6258 abfd = h->root.u.def.section->owner;
6259 break;
6261 case bfd_link_hash_common:
6262 abfd = h->root.u.c.p->section->owner;
6263 break;
6265 BFD_ASSERT (abfd != NULL);
6267 for (loaded = elf_hash_table (info)->loaded;
6268 loaded != NULL;
6269 loaded = loaded->next)
6271 bfd *input;
6272 Elf_Internal_Shdr *hdr;
6273 bfd_size_type symcount;
6274 bfd_size_type extsymcount;
6275 bfd_size_type extsymoff;
6276 Elf_Internal_Shdr *versymhdr;
6277 Elf_Internal_Sym *isym;
6278 Elf_Internal_Sym *isymend;
6279 Elf_Internal_Sym *isymbuf;
6280 Elf_External_Versym *ever;
6281 Elf_External_Versym *extversym;
6283 input = loaded->abfd;
6285 /* We check each DSO for a possible hidden versioned definition. */
6286 if (input == abfd
6287 || (input->flags & DYNAMIC) == 0
6288 || elf_dynversym (input) == 0)
6289 continue;
6291 hdr = &elf_tdata (input)->dynsymtab_hdr;
6293 symcount = hdr->sh_size / bed->s->sizeof_sym;
6294 if (elf_bad_symtab (input))
6296 extsymcount = symcount;
6297 extsymoff = 0;
6299 else
6301 extsymcount = symcount - hdr->sh_info;
6302 extsymoff = hdr->sh_info;
6305 if (extsymcount == 0)
6306 continue;
6308 isymbuf = bfd_elf_get_elf_syms (input, hdr, extsymcount, extsymoff,
6309 NULL, NULL, NULL);
6310 if (isymbuf == NULL)
6311 return FALSE;
6313 /* Read in any version definitions. */
6314 versymhdr = &elf_tdata (input)->dynversym_hdr;
6315 extversym = bfd_malloc (versymhdr->sh_size);
6316 if (extversym == NULL)
6317 goto error_ret;
6319 if (bfd_seek (input, versymhdr->sh_offset, SEEK_SET) != 0
6320 || (bfd_bread (extversym, versymhdr->sh_size, input)
6321 != versymhdr->sh_size))
6323 free (extversym);
6324 error_ret:
6325 free (isymbuf);
6326 return FALSE;
6329 ever = extversym + extsymoff;
6330 isymend = isymbuf + extsymcount;
6331 for (isym = isymbuf; isym < isymend; isym++, ever++)
6333 const char *name;
6334 Elf_Internal_Versym iver;
6335 unsigned short version_index;
6337 if (ELF_ST_BIND (isym->st_info) == STB_LOCAL
6338 || isym->st_shndx == SHN_UNDEF)
6339 continue;
6341 name = bfd_elf_string_from_elf_section (input,
6342 hdr->sh_link,
6343 isym->st_name);
6344 if (strcmp (name, h->root.root.string) != 0)
6345 continue;
6347 _bfd_elf_swap_versym_in (input, ever, &iver);
6349 if ((iver.vs_vers & VERSYM_HIDDEN) == 0)
6351 /* If we have a non-hidden versioned sym, then it should
6352 have provided a definition for the undefined sym. */
6353 abort ();
6356 version_index = iver.vs_vers & VERSYM_VERSION;
6357 if (version_index == 1 || version_index == 2)
6359 /* This is the base or first version. We can use it. */
6360 free (extversym);
6361 free (isymbuf);
6362 return TRUE;
6366 free (extversym);
6367 free (isymbuf);
6370 return FALSE;
6373 /* Add an external symbol to the symbol table. This is called from
6374 the hash table traversal routine. When generating a shared object,
6375 we go through the symbol table twice. The first time we output
6376 anything that might have been forced to local scope in a version
6377 script. The second time we output the symbols that are still
6378 global symbols. */
6380 static bfd_boolean
6381 elf_link_output_extsym (struct elf_link_hash_entry *h, void *data)
6383 struct elf_outext_info *eoinfo = data;
6384 struct elf_final_link_info *finfo = eoinfo->finfo;
6385 bfd_boolean strip;
6386 Elf_Internal_Sym sym;
6387 asection *input_sec;
6388 const struct elf_backend_data *bed;
6390 if (h->root.type == bfd_link_hash_warning)
6392 h = (struct elf_link_hash_entry *) h->root.u.i.link;
6393 if (h->root.type == bfd_link_hash_new)
6394 return TRUE;
6397 /* Decide whether to output this symbol in this pass. */
6398 if (eoinfo->localsyms)
6400 if (!h->forced_local)
6401 return TRUE;
6403 else
6405 if (h->forced_local)
6406 return TRUE;
6409 bed = get_elf_backend_data (finfo->output_bfd);
6411 if (h->root.type == bfd_link_hash_undefined)
6413 /* If we have an undefined symbol reference here then it must have
6414 come from a shared library that is being linked in. (Undefined
6415 references in regular files have already been handled). */
6416 bfd_boolean ignore_undef = FALSE;
6418 /* Some symbols may be special in that the fact that they're
6419 undefined can be safely ignored - let backend determine that. */
6420 if (bed->elf_backend_ignore_undef_symbol)
6421 ignore_undef = bed->elf_backend_ignore_undef_symbol (h);
6423 /* If we are reporting errors for this situation then do so now. */
6424 if (ignore_undef == FALSE
6425 && h->ref_dynamic
6426 && ! h->ref_regular
6427 && ! elf_link_check_versioned_symbol (finfo->info, bed, h)
6428 && finfo->info->unresolved_syms_in_shared_libs != RM_IGNORE)
6430 if (! (finfo->info->callbacks->undefined_symbol
6431 (finfo->info, h->root.root.string, h->root.u.undef.abfd,
6432 NULL, 0, finfo->info->unresolved_syms_in_shared_libs == RM_GENERATE_ERROR)))
6434 eoinfo->failed = TRUE;
6435 return FALSE;
6440 /* We should also warn if a forced local symbol is referenced from
6441 shared libraries. */
6442 if (! finfo->info->relocatable
6443 && (! finfo->info->shared)
6444 && h->forced_local
6445 && h->ref_dynamic
6446 && !h->dynamic_def
6447 && !h->dynamic_weak
6448 && ! elf_link_check_versioned_symbol (finfo->info, bed, h))
6450 (*_bfd_error_handler)
6451 (_("%B: %s symbol `%s' in %B is referenced by DSO"),
6452 finfo->output_bfd,
6453 h->root.u.def.section == bfd_abs_section_ptr
6454 ? finfo->output_bfd : h->root.u.def.section->owner,
6455 ELF_ST_VISIBILITY (h->other) == STV_INTERNAL
6456 ? "internal"
6457 : ELF_ST_VISIBILITY (h->other) == STV_HIDDEN
6458 ? "hidden" : "local",
6459 h->root.root.string);
6460 eoinfo->failed = TRUE;
6461 return FALSE;
6464 /* We don't want to output symbols that have never been mentioned by
6465 a regular file, or that we have been told to strip. However, if
6466 h->indx is set to -2, the symbol is used by a reloc and we must
6467 output it. */
6468 if (h->indx == -2)
6469 strip = FALSE;
6470 else if ((h->def_dynamic
6471 || h->ref_dynamic
6472 || h->root.type == bfd_link_hash_new)
6473 && !h->def_regular
6474 && !h->ref_regular)
6475 strip = TRUE;
6476 else if (finfo->info->strip == strip_all)
6477 strip = TRUE;
6478 else if (finfo->info->strip == strip_some
6479 && bfd_hash_lookup (finfo->info->keep_hash,
6480 h->root.root.string, FALSE, FALSE) == NULL)
6481 strip = TRUE;
6482 else if (finfo->info->strip_discarded
6483 && (h->root.type == bfd_link_hash_defined
6484 || h->root.type == bfd_link_hash_defweak)
6485 && elf_discarded_section (h->root.u.def.section))
6486 strip = TRUE;
6487 else
6488 strip = FALSE;
6490 /* If we're stripping it, and it's not a dynamic symbol, there's
6491 nothing else to do unless it is a forced local symbol. */
6492 if (strip
6493 && h->dynindx == -1
6494 && !h->forced_local)
6495 return TRUE;
6497 sym.st_value = 0;
6498 sym.st_size = h->size;
6499 sym.st_other = h->other;
6500 if (h->forced_local)
6501 sym.st_info = ELF_ST_INFO (STB_LOCAL, h->type);
6502 else if (h->root.type == bfd_link_hash_undefweak
6503 || h->root.type == bfd_link_hash_defweak)
6504 sym.st_info = ELF_ST_INFO (STB_WEAK, h->type);
6505 else
6506 sym.st_info = ELF_ST_INFO (STB_GLOBAL, h->type);
6508 switch (h->root.type)
6510 default:
6511 case bfd_link_hash_new:
6512 case bfd_link_hash_warning:
6513 abort ();
6514 return FALSE;
6516 case bfd_link_hash_undefined:
6517 case bfd_link_hash_undefweak:
6518 input_sec = bfd_und_section_ptr;
6519 sym.st_shndx = SHN_UNDEF;
6520 break;
6522 case bfd_link_hash_defined:
6523 case bfd_link_hash_defweak:
6525 input_sec = h->root.u.def.section;
6526 if (input_sec->output_section != NULL)
6528 sym.st_shndx =
6529 _bfd_elf_section_from_bfd_section (finfo->output_bfd,
6530 input_sec->output_section);
6531 if (sym.st_shndx == SHN_BAD)
6533 (*_bfd_error_handler)
6534 (_("%B: could not find output section %A for input section %A"),
6535 finfo->output_bfd, input_sec->output_section, input_sec);
6536 eoinfo->failed = TRUE;
6537 return FALSE;
6540 /* ELF symbols in relocatable files are section relative,
6541 but in nonrelocatable files they are virtual
6542 addresses. */
6543 sym.st_value = h->root.u.def.value + input_sec->output_offset;
6544 if (! finfo->info->relocatable)
6546 sym.st_value += input_sec->output_section->vma;
6547 if (h->type == STT_TLS)
6549 /* STT_TLS symbols are relative to PT_TLS segment
6550 base. */
6551 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
6552 sym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
6556 else
6558 BFD_ASSERT (input_sec->owner == NULL
6559 || (input_sec->owner->flags & DYNAMIC) != 0);
6560 sym.st_shndx = SHN_UNDEF;
6561 input_sec = bfd_und_section_ptr;
6564 break;
6566 case bfd_link_hash_common:
6567 input_sec = h->root.u.c.p->section;
6568 sym.st_shndx = bed->common_section_index (input_sec);
6569 sym.st_value = 1 << h->root.u.c.p->alignment_power;
6570 break;
6572 case bfd_link_hash_indirect:
6573 /* These symbols are created by symbol versioning. They point
6574 to the decorated version of the name. For example, if the
6575 symbol foo@@GNU_1.2 is the default, which should be used when
6576 foo is used with no version, then we add an indirect symbol
6577 foo which points to foo@@GNU_1.2. We ignore these symbols,
6578 since the indirected symbol is already in the hash table. */
6579 return TRUE;
6582 /* Give the processor backend a chance to tweak the symbol value,
6583 and also to finish up anything that needs to be done for this
6584 symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for
6585 forced local syms when non-shared is due to a historical quirk. */
6586 if ((h->dynindx != -1
6587 || h->forced_local)
6588 && ((finfo->info->shared
6589 && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT
6590 || h->root.type != bfd_link_hash_undefweak))
6591 || !h->forced_local)
6592 && elf_hash_table (finfo->info)->dynamic_sections_created)
6594 if (! ((*bed->elf_backend_finish_dynamic_symbol)
6595 (finfo->output_bfd, finfo->info, h, &sym)))
6597 eoinfo->failed = TRUE;
6598 return FALSE;
6602 /* If we are marking the symbol as undefined, and there are no
6603 non-weak references to this symbol from a regular object, then
6604 mark the symbol as weak undefined; if there are non-weak
6605 references, mark the symbol as strong. We can't do this earlier,
6606 because it might not be marked as undefined until the
6607 finish_dynamic_symbol routine gets through with it. */
6608 if (sym.st_shndx == SHN_UNDEF
6609 && h->ref_regular
6610 && (ELF_ST_BIND (sym.st_info) == STB_GLOBAL
6611 || ELF_ST_BIND (sym.st_info) == STB_WEAK))
6613 int bindtype;
6615 if (h->ref_regular_nonweak)
6616 bindtype = STB_GLOBAL;
6617 else
6618 bindtype = STB_WEAK;
6619 sym.st_info = ELF_ST_INFO (bindtype, ELF_ST_TYPE (sym.st_info));
6622 /* If a non-weak symbol with non-default visibility is not defined
6623 locally, it is a fatal error. */
6624 if (! finfo->info->relocatable
6625 && ELF_ST_VISIBILITY (sym.st_other) != STV_DEFAULT
6626 && ELF_ST_BIND (sym.st_info) != STB_WEAK
6627 && h->root.type == bfd_link_hash_undefined
6628 && !h->def_regular)
6630 (*_bfd_error_handler)
6631 (_("%B: %s symbol `%s' isn't defined"),
6632 finfo->output_bfd,
6633 ELF_ST_VISIBILITY (sym.st_other) == STV_PROTECTED
6634 ? "protected"
6635 : ELF_ST_VISIBILITY (sym.st_other) == STV_INTERNAL
6636 ? "internal" : "hidden",
6637 h->root.root.string);
6638 eoinfo->failed = TRUE;
6639 return FALSE;
6642 /* If this symbol should be put in the .dynsym section, then put it
6643 there now. We already know the symbol index. We also fill in
6644 the entry in the .hash section. */
6645 if (h->dynindx != -1
6646 && elf_hash_table (finfo->info)->dynamic_sections_created)
6648 size_t bucketcount;
6649 size_t bucket;
6650 size_t hash_entry_size;
6651 bfd_byte *bucketpos;
6652 bfd_vma chain;
6653 bfd_byte *esym;
6655 sym.st_name = h->dynstr_index;
6656 esym = finfo->dynsym_sec->contents + h->dynindx * bed->s->sizeof_sym;
6657 if (! check_dynsym (finfo->output_bfd, &sym))
6659 eoinfo->failed = TRUE;
6660 return FALSE;
6662 bed->s->swap_symbol_out (finfo->output_bfd, &sym, esym, 0);
6664 bucketcount = elf_hash_table (finfo->info)->bucketcount;
6665 bucket = h->u.elf_hash_value % bucketcount;
6666 hash_entry_size
6667 = elf_section_data (finfo->hash_sec)->this_hdr.sh_entsize;
6668 bucketpos = ((bfd_byte *) finfo->hash_sec->contents
6669 + (bucket + 2) * hash_entry_size);
6670 chain = bfd_get (8 * hash_entry_size, finfo->output_bfd, bucketpos);
6671 bfd_put (8 * hash_entry_size, finfo->output_bfd, h->dynindx, bucketpos);
6672 bfd_put (8 * hash_entry_size, finfo->output_bfd, chain,
6673 ((bfd_byte *) finfo->hash_sec->contents
6674 + (bucketcount + 2 + h->dynindx) * hash_entry_size));
6676 if (finfo->symver_sec != NULL && finfo->symver_sec->contents != NULL)
6678 Elf_Internal_Versym iversym;
6679 Elf_External_Versym *eversym;
6681 if (!h->def_regular)
6683 if (h->verinfo.verdef == NULL)
6684 iversym.vs_vers = 0;
6685 else
6686 iversym.vs_vers = h->verinfo.verdef->vd_exp_refno + 1;
6688 else
6690 if (h->verinfo.vertree == NULL)
6691 iversym.vs_vers = 1;
6692 else
6693 iversym.vs_vers = h->verinfo.vertree->vernum + 1;
6694 if (finfo->info->create_default_symver)
6695 iversym.vs_vers++;
6698 if (h->hidden)
6699 iversym.vs_vers |= VERSYM_HIDDEN;
6701 eversym = (Elf_External_Versym *) finfo->symver_sec->contents;
6702 eversym += h->dynindx;
6703 _bfd_elf_swap_versym_out (finfo->output_bfd, &iversym, eversym);
6707 /* If we're stripping it, then it was just a dynamic symbol, and
6708 there's nothing else to do. */
6709 if (strip || (input_sec->flags & SEC_EXCLUDE) != 0)
6710 return TRUE;
6712 h->indx = bfd_get_symcount (finfo->output_bfd);
6714 if (! elf_link_output_sym (finfo, h->root.root.string, &sym, input_sec, h))
6716 eoinfo->failed = TRUE;
6717 return FALSE;
6720 return TRUE;
6723 /* Return TRUE if special handling is done for relocs in SEC against
6724 symbols defined in discarded sections. */
6726 static bfd_boolean
6727 elf_section_ignore_discarded_relocs (asection *sec)
6729 const struct elf_backend_data *bed;
6731 switch (sec->sec_info_type)
6733 case ELF_INFO_TYPE_STABS:
6734 case ELF_INFO_TYPE_EH_FRAME:
6735 return TRUE;
6736 default:
6737 break;
6740 bed = get_elf_backend_data (sec->owner);
6741 if (bed->elf_backend_ignore_discarded_relocs != NULL
6742 && (*bed->elf_backend_ignore_discarded_relocs) (sec))
6743 return TRUE;
6745 return FALSE;
6748 /* Return a mask saying how ld should treat relocations in SEC against
6749 symbols defined in discarded sections. If this function returns
6750 COMPLAIN set, ld will issue a warning message. If this function
6751 returns PRETEND set, and the discarded section was link-once and the
6752 same size as the kept link-once section, ld will pretend that the
6753 symbol was actually defined in the kept section. Otherwise ld will
6754 zero the reloc (at least that is the intent, but some cooperation by
6755 the target dependent code is needed, particularly for REL targets). */
6757 unsigned int
6758 _bfd_elf_default_action_discarded (asection *sec)
6760 if (sec->flags & SEC_DEBUGGING)
6761 return 0;
6763 if (strcmp (".eh_frame", sec->name) == 0)
6764 return 0;
6766 if (strcmp (".gcc_except_table", sec->name) == 0)
6767 return 0;
6769 return COMPLAIN | PRETEND;
6772 /* Find a match between a section and a member of a section group. */
6774 static asection *
6775 match_group_member (asection *sec, asection *group)
6777 asection *first = elf_next_in_group (group);
6778 asection *s = first;
6780 while (s != NULL)
6782 if (bfd_elf_match_symbols_in_sections (s, sec))
6783 return s;
6785 if (s == first)
6786 break;
6789 return NULL;
6792 /* Check if the kept section of a discarded section SEC can be used
6793 to replace it. Return the replacement if it is OK. Otherwise return
6794 NULL. */
6796 asection *
6797 _bfd_elf_check_kept_section (asection *sec)
6799 asection *kept;
6801 kept = sec->kept_section;
6802 if (kept != NULL)
6804 if (elf_sec_group (sec) != NULL)
6805 kept = match_group_member (sec, kept);
6806 if (kept != NULL && sec->size != kept->size)
6807 kept = NULL;
6809 return kept;
6812 /* Link an input file into the linker output file. This function
6813 handles all the sections and relocations of the input file at once.
6814 This is so that we only have to read the local symbols once, and
6815 don't have to keep them in memory. */
6817 static bfd_boolean
6818 elf_link_input_bfd (struct elf_final_link_info *finfo, bfd *input_bfd)
6820 bfd_boolean (*relocate_section)
6821 (bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
6822 Elf_Internal_Rela *, Elf_Internal_Sym *, asection **);
6823 bfd *output_bfd;
6824 Elf_Internal_Shdr *symtab_hdr;
6825 size_t locsymcount;
6826 size_t extsymoff;
6827 Elf_Internal_Sym *isymbuf;
6828 Elf_Internal_Sym *isym;
6829 Elf_Internal_Sym *isymend;
6830 long *pindex;
6831 asection **ppsection;
6832 asection *o;
6833 const struct elf_backend_data *bed;
6834 bfd_boolean emit_relocs;
6835 struct elf_link_hash_entry **sym_hashes;
6837 output_bfd = finfo->output_bfd;
6838 bed = get_elf_backend_data (output_bfd);
6839 relocate_section = bed->elf_backend_relocate_section;
6841 /* If this is a dynamic object, we don't want to do anything here:
6842 we don't want the local symbols, and we don't want the section
6843 contents. */
6844 if ((input_bfd->flags & DYNAMIC) != 0)
6845 return TRUE;
6847 emit_relocs = (finfo->info->relocatable
6848 || finfo->info->emitrelocations);
6850 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
6851 if (elf_bad_symtab (input_bfd))
6853 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
6854 extsymoff = 0;
6856 else
6858 locsymcount = symtab_hdr->sh_info;
6859 extsymoff = symtab_hdr->sh_info;
6862 /* Read the local symbols. */
6863 isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
6864 if (isymbuf == NULL && locsymcount != 0)
6866 isymbuf = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, locsymcount, 0,
6867 finfo->internal_syms,
6868 finfo->external_syms,
6869 finfo->locsym_shndx);
6870 if (isymbuf == NULL)
6871 return FALSE;
6874 /* Find local symbol sections and adjust values of symbols in
6875 SEC_MERGE sections. Write out those local symbols we know are
6876 going into the output file. */
6877 isymend = isymbuf + locsymcount;
6878 for (isym = isymbuf, pindex = finfo->indices, ppsection = finfo->sections;
6879 isym < isymend;
6880 isym++, pindex++, ppsection++)
6882 asection *isec;
6883 const char *name;
6884 Elf_Internal_Sym osym;
6886 *pindex = -1;
6888 if (elf_bad_symtab (input_bfd))
6890 if (ELF_ST_BIND (isym->st_info) != STB_LOCAL)
6892 *ppsection = NULL;
6893 continue;
6897 if (isym->st_shndx == SHN_UNDEF)
6898 isec = bfd_und_section_ptr;
6899 else if (isym->st_shndx < SHN_LORESERVE
6900 || isym->st_shndx > SHN_HIRESERVE)
6902 isec = bfd_section_from_elf_index (input_bfd, isym->st_shndx);
6903 if (isec
6904 && isec->sec_info_type == ELF_INFO_TYPE_MERGE
6905 && ELF_ST_TYPE (isym->st_info) != STT_SECTION)
6906 isym->st_value =
6907 _bfd_merged_section_offset (output_bfd, &isec,
6908 elf_section_data (isec)->sec_info,
6909 isym->st_value);
6911 else if (isym->st_shndx == SHN_ABS)
6912 isec = bfd_abs_section_ptr;
6913 else if (isym->st_shndx == SHN_COMMON)
6914 isec = bfd_com_section_ptr;
6915 else
6917 /* Don't attempt to output symbols with st_shnx in the
6918 reserved range other than SHN_ABS and SHN_COMMON. */
6919 *ppsection = NULL;
6920 continue;
6923 *ppsection = isec;
6925 /* Don't output the first, undefined, symbol. */
6926 if (ppsection == finfo->sections)
6927 continue;
6929 if (ELF_ST_TYPE (isym->st_info) == STT_SECTION)
6931 /* We never output section symbols. Instead, we use the
6932 section symbol of the corresponding section in the output
6933 file. */
6934 continue;
6937 /* If we are stripping all symbols, we don't want to output this
6938 one. */
6939 if (finfo->info->strip == strip_all)
6940 continue;
6942 /* If we are discarding all local symbols, we don't want to
6943 output this one. If we are generating a relocatable output
6944 file, then some of the local symbols may be required by
6945 relocs; we output them below as we discover that they are
6946 needed. */
6947 if (finfo->info->discard == discard_all)
6948 continue;
6950 /* If this symbol is defined in a section which we are
6951 discarding, we don't need to keep it. */
6952 if (isym->st_shndx != SHN_UNDEF
6953 && (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
6954 && (isec == NULL
6955 || bfd_section_removed_from_list (output_bfd,
6956 isec->output_section)))
6957 continue;
6959 /* Get the name of the symbol. */
6960 name = bfd_elf_string_from_elf_section (input_bfd, symtab_hdr->sh_link,
6961 isym->st_name);
6962 if (name == NULL)
6963 return FALSE;
6965 /* See if we are discarding symbols with this name. */
6966 if ((finfo->info->strip == strip_some
6967 && (bfd_hash_lookup (finfo->info->keep_hash, name, FALSE, FALSE)
6968 == NULL))
6969 || (((finfo->info->discard == discard_sec_merge
6970 && (isec->flags & SEC_MERGE) && ! finfo->info->relocatable)
6971 || finfo->info->discard == discard_l)
6972 && bfd_is_local_label_name (input_bfd, name)))
6973 continue;
6975 /* If we get here, we are going to output this symbol. */
6977 osym = *isym;
6979 /* Adjust the section index for the output file. */
6980 osym.st_shndx = _bfd_elf_section_from_bfd_section (output_bfd,
6981 isec->output_section);
6982 if (osym.st_shndx == SHN_BAD)
6983 return FALSE;
6985 *pindex = bfd_get_symcount (output_bfd);
6987 /* ELF symbols in relocatable files are section relative, but
6988 in executable files they are virtual addresses. Note that
6989 this code assumes that all ELF sections have an associated
6990 BFD section with a reasonable value for output_offset; below
6991 we assume that they also have a reasonable value for
6992 output_section. Any special sections must be set up to meet
6993 these requirements. */
6994 osym.st_value += isec->output_offset;
6995 if (! finfo->info->relocatable)
6997 osym.st_value += isec->output_section->vma;
6998 if (ELF_ST_TYPE (osym.st_info) == STT_TLS)
7000 /* STT_TLS symbols are relative to PT_TLS segment base. */
7001 BFD_ASSERT (elf_hash_table (finfo->info)->tls_sec != NULL);
7002 osym.st_value -= elf_hash_table (finfo->info)->tls_sec->vma;
7006 if (! elf_link_output_sym (finfo, name, &osym, isec, NULL))
7007 return FALSE;
7010 /* Relocate the contents of each section. */
7011 sym_hashes = elf_sym_hashes (input_bfd);
7012 for (o = input_bfd->sections; o != NULL; o = o->next)
7014 bfd_byte *contents;
7016 if (! o->linker_mark)
7018 /* This section was omitted from the link. */
7019 continue;
7022 if ((o->flags & SEC_HAS_CONTENTS) == 0
7023 || (o->size == 0 && (o->flags & SEC_RELOC) == 0))
7024 continue;
7026 if ((o->flags & SEC_LINKER_CREATED) != 0)
7028 /* Section was created by _bfd_elf_link_create_dynamic_sections
7029 or somesuch. */
7030 continue;
7033 /* Get the contents of the section. They have been cached by a
7034 relaxation routine. Note that o is a section in an input
7035 file, so the contents field will not have been set by any of
7036 the routines which work on output files. */
7037 if (elf_section_data (o)->this_hdr.contents != NULL)
7038 contents = elf_section_data (o)->this_hdr.contents;
7039 else
7041 bfd_size_type amt = o->rawsize ? o->rawsize : o->size;
7043 contents = finfo->contents;
7044 if (! bfd_get_section_contents (input_bfd, o, contents, 0, amt))
7045 return FALSE;
7048 if ((o->flags & SEC_RELOC) != 0)
7050 Elf_Internal_Rela *internal_relocs;
7051 bfd_vma r_type_mask;
7052 int r_sym_shift;
7054 /* Get the swapped relocs. */
7055 internal_relocs
7056 = _bfd_elf_link_read_relocs (input_bfd, o, finfo->external_relocs,
7057 finfo->internal_relocs, FALSE);
7058 if (internal_relocs == NULL
7059 && o->reloc_count > 0)
7060 return FALSE;
7062 if (bed->s->arch_size == 32)
7064 r_type_mask = 0xff;
7065 r_sym_shift = 8;
7067 else
7069 r_type_mask = 0xffffffff;
7070 r_sym_shift = 32;
7073 /* Run through the relocs looking for any against symbols
7074 from discarded sections and section symbols from
7075 removed link-once sections. Complain about relocs
7076 against discarded sections. Zero relocs against removed
7077 link-once sections. */
7078 if (!elf_section_ignore_discarded_relocs (o))
7080 Elf_Internal_Rela *rel, *relend;
7081 unsigned int action = (*bed->action_discarded) (o);
7083 rel = internal_relocs;
7084 relend = rel + o->reloc_count * bed->s->int_rels_per_ext_rel;
7085 for ( ; rel < relend; rel++)
7087 unsigned long r_symndx = rel->r_info >> r_sym_shift;
7088 asection **ps, *sec;
7089 struct elf_link_hash_entry *h = NULL;
7090 const char *sym_name;
7092 if (r_symndx == STN_UNDEF)
7093 continue;
7095 if (r_symndx >= locsymcount
7096 || (elf_bad_symtab (input_bfd)
7097 && finfo->sections[r_symndx] == NULL))
7099 h = sym_hashes[r_symndx - extsymoff];
7101 /* Badly formatted input files can contain relocs that
7102 reference non-existant symbols. Check here so that
7103 we do not seg fault. */
7104 if (h == NULL)
7106 char buffer [32];
7108 sprintf_vma (buffer, rel->r_info);
7109 (*_bfd_error_handler)
7110 (_("error: %B contains a reloc (0x%s) for section %A "
7111 "that references a non-existent global symbol"),
7112 input_bfd, o, buffer);
7113 bfd_set_error (bfd_error_bad_value);
7114 return FALSE;
7117 while (h->root.type == bfd_link_hash_indirect
7118 || h->root.type == bfd_link_hash_warning)
7119 h = (struct elf_link_hash_entry *) h->root.u.i.link;
7121 if (h->root.type != bfd_link_hash_defined
7122 && h->root.type != bfd_link_hash_defweak)
7123 continue;
7125 ps = &h->root.u.def.section;
7126 sym_name = h->root.root.string;
7128 else
7130 Elf_Internal_Sym *sym = isymbuf + r_symndx;
7131 ps = &finfo->sections[r_symndx];
7132 sym_name = bfd_elf_sym_name (input_bfd,
7133 symtab_hdr,
7134 sym, *ps);
7137 /* Complain if the definition comes from a
7138 discarded section. */
7139 if ((sec = *ps) != NULL && elf_discarded_section (sec))
7141 BFD_ASSERT (r_symndx != 0);
7142 if (action & COMPLAIN)
7143 (*finfo->info->callbacks->einfo)
7144 (_("%X`%s' referenced in section `%A' of %B: "
7145 "defined in discarded section `%A' of %B\n"),
7146 sym_name, o, input_bfd, sec, sec->owner);
7148 /* Try to do the best we can to support buggy old
7149 versions of gcc. Pretend that the symbol is
7150 really defined in the kept linkonce section.
7151 FIXME: This is quite broken. Modifying the
7152 symbol here means we will be changing all later
7153 uses of the symbol, not just in this section. */
7154 if (action & PRETEND)
7156 asection *kept;
7158 kept = _bfd_elf_check_kept_section (sec);
7159 if (kept != NULL)
7161 *ps = kept;
7162 continue;
7166 /* Remove the symbol reference from the reloc, but
7167 don't kill the reloc completely. This is so that
7168 a zero value will be written into the section,
7169 which may have non-zero contents put there by the
7170 assembler. Zero in things like an eh_frame fde
7171 pc_begin allows stack unwinders to recognize the
7172 fde as bogus. */
7173 rel->r_info &= r_type_mask;
7174 rel->r_addend = 0;
7179 /* Relocate the section by invoking a back end routine.
7181 The back end routine is responsible for adjusting the
7182 section contents as necessary, and (if using Rela relocs
7183 and generating a relocatable output file) adjusting the
7184 reloc addend as necessary.
7186 The back end routine does not have to worry about setting
7187 the reloc address or the reloc symbol index.
7189 The back end routine is given a pointer to the swapped in
7190 internal symbols, and can access the hash table entries
7191 for the external symbols via elf_sym_hashes (input_bfd).
7193 When generating relocatable output, the back end routine
7194 must handle STB_LOCAL/STT_SECTION symbols specially. The
7195 output symbol is going to be a section symbol
7196 corresponding to the output section, which will require
7197 the addend to be adjusted. */
7199 if (! (*relocate_section) (output_bfd, finfo->info,
7200 input_bfd, o, contents,
7201 internal_relocs,
7202 isymbuf,
7203 finfo->sections))
7204 return FALSE;
7206 if (emit_relocs)
7208 Elf_Internal_Rela *irela;
7209 Elf_Internal_Rela *irelaend;
7210 bfd_vma last_offset;
7211 struct elf_link_hash_entry **rel_hash;
7212 struct elf_link_hash_entry **rel_hash_list;
7213 Elf_Internal_Shdr *input_rel_hdr, *input_rel_hdr2;
7214 unsigned int next_erel;
7215 bfd_boolean rela_normal;
7217 input_rel_hdr = &elf_section_data (o)->rel_hdr;
7218 rela_normal = (bed->rela_normal
7219 && (input_rel_hdr->sh_entsize
7220 == bed->s->sizeof_rela));
7222 /* Adjust the reloc addresses and symbol indices. */
7224 irela = internal_relocs;
7225 irelaend = irela + o->reloc_count * bed->s->int_rels_per_ext_rel;
7226 rel_hash = (elf_section_data (o->output_section)->rel_hashes
7227 + elf_section_data (o->output_section)->rel_count
7228 + elf_section_data (o->output_section)->rel_count2);
7229 rel_hash_list = rel_hash;
7230 last_offset = o->output_offset;
7231 if (!finfo->info->relocatable)
7232 last_offset += o->output_section->vma;
7233 for (next_erel = 0; irela < irelaend; irela++, next_erel++)
7235 unsigned long r_symndx;
7236 asection *sec;
7237 Elf_Internal_Sym sym;
7239 if (next_erel == bed->s->int_rels_per_ext_rel)
7241 rel_hash++;
7242 next_erel = 0;
7245 irela->r_offset = _bfd_elf_section_offset (output_bfd,
7246 finfo->info, o,
7247 irela->r_offset);
7248 if (irela->r_offset >= (bfd_vma) -2)
7250 /* This is a reloc for a deleted entry or somesuch.
7251 Turn it into an R_*_NONE reloc, at the same
7252 offset as the last reloc. elf_eh_frame.c and
7253 bfd_elf_discard_info rely on reloc offsets
7254 being ordered. */
7255 irela->r_offset = last_offset;
7256 irela->r_info = 0;
7257 irela->r_addend = 0;
7258 continue;
7261 irela->r_offset += o->output_offset;
7263 /* Relocs in an executable have to be virtual addresses. */
7264 if (!finfo->info->relocatable)
7265 irela->r_offset += o->output_section->vma;
7267 last_offset = irela->r_offset;
7269 r_symndx = irela->r_info >> r_sym_shift;
7270 if (r_symndx == STN_UNDEF)
7271 continue;
7273 if (r_symndx >= locsymcount
7274 || (elf_bad_symtab (input_bfd)
7275 && finfo->sections[r_symndx] == NULL))
7277 struct elf_link_hash_entry *rh;
7278 unsigned long indx;
7280 /* This is a reloc against a global symbol. We
7281 have not yet output all the local symbols, so
7282 we do not know the symbol index of any global
7283 symbol. We set the rel_hash entry for this
7284 reloc to point to the global hash table entry
7285 for this symbol. The symbol index is then
7286 set at the end of bfd_elf_final_link. */
7287 indx = r_symndx - extsymoff;
7288 rh = elf_sym_hashes (input_bfd)[indx];
7289 while (rh->root.type == bfd_link_hash_indirect
7290 || rh->root.type == bfd_link_hash_warning)
7291 rh = (struct elf_link_hash_entry *) rh->root.u.i.link;
7293 /* Setting the index to -2 tells
7294 elf_link_output_extsym that this symbol is
7295 used by a reloc. */
7296 BFD_ASSERT (rh->indx < 0);
7297 rh->indx = -2;
7299 *rel_hash = rh;
7301 continue;
7304 /* This is a reloc against a local symbol. */
7306 *rel_hash = NULL;
7307 sym = isymbuf[r_symndx];
7308 sec = finfo->sections[r_symndx];
7309 if (ELF_ST_TYPE (sym.st_info) == STT_SECTION)
7311 /* I suppose the backend ought to fill in the
7312 section of any STT_SECTION symbol against a
7313 processor specific section. */
7314 r_symndx = 0;
7315 if (bfd_is_abs_section (sec))
7317 else if (sec == NULL || sec->owner == NULL)
7319 bfd_set_error (bfd_error_bad_value);
7320 return FALSE;
7322 else
7324 asection *osec = sec->output_section;
7326 /* If we have discarded a section, the output
7327 section will be the absolute section. In
7328 case of discarded link-once and discarded
7329 SEC_MERGE sections, use the kept section. */
7330 if (bfd_is_abs_section (osec)
7331 && sec->kept_section != NULL
7332 && sec->kept_section->output_section != NULL)
7334 osec = sec->kept_section->output_section;
7335 irela->r_addend -= osec->vma;
7338 if (!bfd_is_abs_section (osec))
7340 r_symndx = osec->target_index;
7341 BFD_ASSERT (r_symndx != 0);
7345 /* Adjust the addend according to where the
7346 section winds up in the output section. */
7347 if (rela_normal)
7348 irela->r_addend += sec->output_offset;
7350 else
7352 if (finfo->indices[r_symndx] == -1)
7354 unsigned long shlink;
7355 const char *name;
7356 asection *osec;
7358 if (finfo->info->strip == strip_all)
7360 /* You can't do ld -r -s. */
7361 bfd_set_error (bfd_error_invalid_operation);
7362 return FALSE;
7365 /* This symbol was skipped earlier, but
7366 since it is needed by a reloc, we
7367 must output it now. */
7368 shlink = symtab_hdr->sh_link;
7369 name = (bfd_elf_string_from_elf_section
7370 (input_bfd, shlink, sym.st_name));
7371 if (name == NULL)
7372 return FALSE;
7374 osec = sec->output_section;
7375 sym.st_shndx =
7376 _bfd_elf_section_from_bfd_section (output_bfd,
7377 osec);
7378 if (sym.st_shndx == SHN_BAD)
7379 return FALSE;
7381 sym.st_value += sec->output_offset;
7382 if (! finfo->info->relocatable)
7384 sym.st_value += osec->vma;
7385 if (ELF_ST_TYPE (sym.st_info) == STT_TLS)
7387 /* STT_TLS symbols are relative to PT_TLS
7388 segment base. */
7389 BFD_ASSERT (elf_hash_table (finfo->info)
7390 ->tls_sec != NULL);
7391 sym.st_value -= (elf_hash_table (finfo->info)
7392 ->tls_sec->vma);
7396 finfo->indices[r_symndx]
7397 = bfd_get_symcount (output_bfd);
7399 if (! elf_link_output_sym (finfo, name, &sym, sec,
7400 NULL))
7401 return FALSE;
7404 r_symndx = finfo->indices[r_symndx];
7407 irela->r_info = ((bfd_vma) r_symndx << r_sym_shift
7408 | (irela->r_info & r_type_mask));
7411 /* Swap out the relocs. */
7412 if (input_rel_hdr->sh_size != 0
7413 && !bed->elf_backend_emit_relocs (output_bfd, o,
7414 input_rel_hdr,
7415 internal_relocs,
7416 rel_hash_list))
7417 return FALSE;
7419 input_rel_hdr2 = elf_section_data (o)->rel_hdr2;
7420 if (input_rel_hdr2 && input_rel_hdr2->sh_size != 0)
7422 internal_relocs += (NUM_SHDR_ENTRIES (input_rel_hdr)
7423 * bed->s->int_rels_per_ext_rel);
7424 rel_hash_list += NUM_SHDR_ENTRIES (input_rel_hdr);
7425 if (!bed->elf_backend_emit_relocs (output_bfd, o,
7426 input_rel_hdr2,
7427 internal_relocs,
7428 rel_hash_list))
7429 return FALSE;
7434 /* Write out the modified section contents. */
7435 if (bed->elf_backend_write_section
7436 && (*bed->elf_backend_write_section) (output_bfd, o, contents))
7438 /* Section written out. */
7440 else switch (o->sec_info_type)
7442 case ELF_INFO_TYPE_STABS:
7443 if (! (_bfd_write_section_stabs
7444 (output_bfd,
7445 &elf_hash_table (finfo->info)->stab_info,
7446 o, &elf_section_data (o)->sec_info, contents)))
7447 return FALSE;
7448 break;
7449 case ELF_INFO_TYPE_MERGE:
7450 if (! _bfd_write_merged_section (output_bfd, o,
7451 elf_section_data (o)->sec_info))
7452 return FALSE;
7453 break;
7454 case ELF_INFO_TYPE_EH_FRAME:
7456 if (! _bfd_elf_write_section_eh_frame (output_bfd, finfo->info,
7457 o, contents))
7458 return FALSE;
7460 break;
7461 default:
7463 if (! (o->flags & SEC_EXCLUDE)
7464 && ! bfd_set_section_contents (output_bfd, o->output_section,
7465 contents,
7466 (file_ptr) o->output_offset,
7467 o->size))
7468 return FALSE;
7470 break;
7474 return TRUE;
7477 /* Generate a reloc when linking an ELF file. This is a reloc
7478 requested by the linker, and does not come from any input file. This
7479 is used to build constructor and destructor tables when linking
7480 with -Ur. */
7482 static bfd_boolean
7483 elf_reloc_link_order (bfd *output_bfd,
7484 struct bfd_link_info *info,
7485 asection *output_section,
7486 struct bfd_link_order *link_order)
7488 reloc_howto_type *howto;
7489 long indx;
7490 bfd_vma offset;
7491 bfd_vma addend;
7492 struct elf_link_hash_entry **rel_hash_ptr;
7493 Elf_Internal_Shdr *rel_hdr;
7494 const struct elf_backend_data *bed = get_elf_backend_data (output_bfd);
7495 Elf_Internal_Rela irel[MAX_INT_RELS_PER_EXT_REL];
7496 bfd_byte *erel;
7497 unsigned int i;
7499 howto = bfd_reloc_type_lookup (output_bfd, link_order->u.reloc.p->reloc);
7500 if (howto == NULL)
7502 bfd_set_error (bfd_error_bad_value);
7503 return FALSE;
7506 addend = link_order->u.reloc.p->addend;
7508 /* Figure out the symbol index. */
7509 rel_hash_ptr = (elf_section_data (output_section)->rel_hashes
7510 + elf_section_data (output_section)->rel_count
7511 + elf_section_data (output_section)->rel_count2);
7512 if (link_order->type == bfd_section_reloc_link_order)
7514 indx = link_order->u.reloc.p->u.section->target_index;
7515 BFD_ASSERT (indx != 0);
7516 *rel_hash_ptr = NULL;
7518 else
7520 struct elf_link_hash_entry *h;
7522 /* Treat a reloc against a defined symbol as though it were
7523 actually against the section. */
7524 h = ((struct elf_link_hash_entry *)
7525 bfd_wrapped_link_hash_lookup (output_bfd, info,
7526 link_order->u.reloc.p->u.name,
7527 FALSE, FALSE, TRUE));
7528 if (h != NULL
7529 && (h->root.type == bfd_link_hash_defined
7530 || h->root.type == bfd_link_hash_defweak))
7532 asection *section;
7534 section = h->root.u.def.section;
7535 indx = section->output_section->target_index;
7536 *rel_hash_ptr = NULL;
7537 /* It seems that we ought to add the symbol value to the
7538 addend here, but in practice it has already been added
7539 because it was passed to constructor_callback. */
7540 addend += section->output_section->vma + section->output_offset;
7542 else if (h != NULL)
7544 /* Setting the index to -2 tells elf_link_output_extsym that
7545 this symbol is used by a reloc. */
7546 h->indx = -2;
7547 *rel_hash_ptr = h;
7548 indx = 0;
7550 else
7552 if (! ((*info->callbacks->unattached_reloc)
7553 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
7554 return FALSE;
7555 indx = 0;
7559 /* If this is an inplace reloc, we must write the addend into the
7560 object file. */
7561 if (howto->partial_inplace && addend != 0)
7563 bfd_size_type size;
7564 bfd_reloc_status_type rstat;
7565 bfd_byte *buf;
7566 bfd_boolean ok;
7567 const char *sym_name;
7569 size = bfd_get_reloc_size (howto);
7570 buf = bfd_zmalloc (size);
7571 if (buf == NULL)
7572 return FALSE;
7573 rstat = _bfd_relocate_contents (howto, output_bfd, addend, buf);
7574 switch (rstat)
7576 case bfd_reloc_ok:
7577 break;
7579 default:
7580 case bfd_reloc_outofrange:
7581 abort ();
7583 case bfd_reloc_overflow:
7584 if (link_order->type == bfd_section_reloc_link_order)
7585 sym_name = bfd_section_name (output_bfd,
7586 link_order->u.reloc.p->u.section);
7587 else
7588 sym_name = link_order->u.reloc.p->u.name;
7589 if (! ((*info->callbacks->reloc_overflow)
7590 (info, NULL, sym_name, howto->name, addend, NULL,
7591 NULL, (bfd_vma) 0)))
7593 free (buf);
7594 return FALSE;
7596 break;
7598 ok = bfd_set_section_contents (output_bfd, output_section, buf,
7599 link_order->offset, size);
7600 free (buf);
7601 if (! ok)
7602 return FALSE;
7605 /* The address of a reloc is relative to the section in a
7606 relocatable file, and is a virtual address in an executable
7607 file. */
7608 offset = link_order->offset;
7609 if (! info->relocatable)
7610 offset += output_section->vma;
7612 for (i = 0; i < bed->s->int_rels_per_ext_rel; i++)
7614 irel[i].r_offset = offset;
7615 irel[i].r_info = 0;
7616 irel[i].r_addend = 0;
7618 if (bed->s->arch_size == 32)
7619 irel[0].r_info = ELF32_R_INFO (indx, howto->type);
7620 else
7621 irel[0].r_info = ELF64_R_INFO (indx, howto->type);
7623 rel_hdr = &elf_section_data (output_section)->rel_hdr;
7624 erel = rel_hdr->contents;
7625 if (rel_hdr->sh_type == SHT_REL)
7627 erel += (elf_section_data (output_section)->rel_count
7628 * bed->s->sizeof_rel);
7629 (*bed->s->swap_reloc_out) (output_bfd, irel, erel);
7631 else
7633 irel[0].r_addend = addend;
7634 erel += (elf_section_data (output_section)->rel_count
7635 * bed->s->sizeof_rela);
7636 (*bed->s->swap_reloca_out) (output_bfd, irel, erel);
7639 ++elf_section_data (output_section)->rel_count;
7641 return TRUE;
7645 /* Get the output vma of the section pointed to by the sh_link field. */
7647 static bfd_vma
7648 elf_get_linked_section_vma (struct bfd_link_order *p)
7650 Elf_Internal_Shdr **elf_shdrp;
7651 asection *s;
7652 int elfsec;
7654 s = p->u.indirect.section;
7655 elf_shdrp = elf_elfsections (s->owner);
7656 elfsec = _bfd_elf_section_from_bfd_section (s->owner, s);
7657 elfsec = elf_shdrp[elfsec]->sh_link;
7658 /* PR 290:
7659 The Intel C compiler generates SHT_IA_64_UNWIND with
7660 SHF_LINK_ORDER. But it doesn't set the sh_link or
7661 sh_info fields. Hence we could get the situation
7662 where elfsec is 0. */
7663 if (elfsec == 0)
7665 const struct elf_backend_data *bed
7666 = get_elf_backend_data (s->owner);
7667 if (bed->link_order_error_handler)
7668 bed->link_order_error_handler
7669 (_("%B: warning: sh_link not set for section `%A'"), s->owner, s);
7670 return 0;
7672 else
7674 s = elf_shdrp[elfsec]->bfd_section;
7675 return s->output_section->vma + s->output_offset;
7680 /* Compare two sections based on the locations of the sections they are
7681 linked to. Used by elf_fixup_link_order. */
7683 static int
7684 compare_link_order (const void * a, const void * b)
7686 bfd_vma apos;
7687 bfd_vma bpos;
7689 apos = elf_get_linked_section_vma (*(struct bfd_link_order **)a);
7690 bpos = elf_get_linked_section_vma (*(struct bfd_link_order **)b);
7691 if (apos < bpos)
7692 return -1;
7693 return apos > bpos;
7697 /* Looks for sections with SHF_LINK_ORDER set. Rearranges them into the same
7698 order as their linked sections. Returns false if this could not be done
7699 because an output section includes both ordered and unordered
7700 sections. Ideally we'd do this in the linker proper. */
7702 static bfd_boolean
7703 elf_fixup_link_order (bfd *abfd, asection *o)
7705 int seen_linkorder;
7706 int seen_other;
7707 int n;
7708 struct bfd_link_order *p;
7709 bfd *sub;
7710 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7711 unsigned elfsec;
7712 struct bfd_link_order **sections;
7713 asection *s, *other_sec, *linkorder_sec;
7714 bfd_vma offset;
7716 other_sec = NULL;
7717 linkorder_sec = NULL;
7718 seen_other = 0;
7719 seen_linkorder = 0;
7720 for (p = o->map_head.link_order; p != NULL; p = p->next)
7722 if (p->type == bfd_indirect_link_order)
7724 s = p->u.indirect.section;
7725 sub = s->owner;
7726 if (bfd_get_flavour (sub) == bfd_target_elf_flavour
7727 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass
7728 && (elfsec = _bfd_elf_section_from_bfd_section (sub, s))
7729 && elfsec < elf_numsections (sub)
7730 && elf_elfsections (sub)[elfsec]->sh_flags & SHF_LINK_ORDER)
7732 seen_linkorder++;
7733 linkorder_sec = s;
7735 else
7737 seen_other++;
7738 other_sec = s;
7741 else
7742 seen_other++;
7744 if (seen_other && seen_linkorder)
7746 if (other_sec && linkorder_sec)
7747 (*_bfd_error_handler) (_("%A has both ordered [`%A' in %B] and unordered [`%A' in %B] sections"),
7748 o, linkorder_sec,
7749 linkorder_sec->owner, other_sec,
7750 other_sec->owner);
7751 else
7752 (*_bfd_error_handler) (_("%A has both ordered and unordered sections"),
7754 bfd_set_error (bfd_error_bad_value);
7755 return FALSE;
7759 if (!seen_linkorder)
7760 return TRUE;
7762 sections = (struct bfd_link_order **)
7763 xmalloc (seen_linkorder * sizeof (struct bfd_link_order *));
7764 seen_linkorder = 0;
7766 for (p = o->map_head.link_order; p != NULL; p = p->next)
7768 sections[seen_linkorder++] = p;
7770 /* Sort the input sections in the order of their linked section. */
7771 qsort (sections, seen_linkorder, sizeof (struct bfd_link_order *),
7772 compare_link_order);
7774 /* Change the offsets of the sections. */
7775 offset = 0;
7776 for (n = 0; n < seen_linkorder; n++)
7778 s = sections[n]->u.indirect.section;
7779 offset &= ~(bfd_vma)((1 << s->alignment_power) - 1);
7780 s->output_offset = offset;
7781 sections[n]->offset = offset;
7782 offset += sections[n]->size;
7785 return TRUE;
7789 /* Do the final step of an ELF link. */
7791 bfd_boolean
7792 bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
7794 bfd_boolean dynamic;
7795 bfd_boolean emit_relocs;
7796 bfd *dynobj;
7797 struct elf_final_link_info finfo;
7798 register asection *o;
7799 register struct bfd_link_order *p;
7800 register bfd *sub;
7801 bfd_size_type max_contents_size;
7802 bfd_size_type max_external_reloc_size;
7803 bfd_size_type max_internal_reloc_count;
7804 bfd_size_type max_sym_count;
7805 bfd_size_type max_sym_shndx_count;
7806 file_ptr off;
7807 Elf_Internal_Sym elfsym;
7808 unsigned int i;
7809 Elf_Internal_Shdr *symtab_hdr;
7810 Elf_Internal_Shdr *symtab_shndx_hdr;
7811 Elf_Internal_Shdr *symstrtab_hdr;
7812 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
7813 struct elf_outext_info eoinfo;
7814 bfd_boolean merged;
7815 size_t relativecount = 0;
7816 asection *reldyn = 0;
7817 bfd_size_type amt;
7819 if (! is_elf_hash_table (info->hash))
7820 return FALSE;
7822 if (info->shared)
7823 abfd->flags |= DYNAMIC;
7825 dynamic = elf_hash_table (info)->dynamic_sections_created;
7826 dynobj = elf_hash_table (info)->dynobj;
7828 emit_relocs = (info->relocatable
7829 || info->emitrelocations);
7831 finfo.info = info;
7832 finfo.output_bfd = abfd;
7833 finfo.symstrtab = _bfd_elf_stringtab_init ();
7834 if (finfo.symstrtab == NULL)
7835 return FALSE;
7837 if (! dynamic)
7839 finfo.dynsym_sec = NULL;
7840 finfo.hash_sec = NULL;
7841 finfo.symver_sec = NULL;
7843 else
7845 finfo.dynsym_sec = bfd_get_section_by_name (dynobj, ".dynsym");
7846 finfo.hash_sec = bfd_get_section_by_name (dynobj, ".hash");
7847 BFD_ASSERT (finfo.dynsym_sec != NULL && finfo.hash_sec != NULL);
7848 finfo.symver_sec = bfd_get_section_by_name (dynobj, ".gnu.version");
7849 /* Note that it is OK if symver_sec is NULL. */
7852 finfo.contents = NULL;
7853 finfo.external_relocs = NULL;
7854 finfo.internal_relocs = NULL;
7855 finfo.external_syms = NULL;
7856 finfo.locsym_shndx = NULL;
7857 finfo.internal_syms = NULL;
7858 finfo.indices = NULL;
7859 finfo.sections = NULL;
7860 finfo.symbuf = NULL;
7861 finfo.symshndxbuf = NULL;
7862 finfo.symbuf_count = 0;
7863 finfo.shndxbuf_size = 0;
7865 /* Count up the number of relocations we will output for each output
7866 section, so that we know the sizes of the reloc sections. We
7867 also figure out some maximum sizes. */
7868 max_contents_size = 0;
7869 max_external_reloc_size = 0;
7870 max_internal_reloc_count = 0;
7871 max_sym_count = 0;
7872 max_sym_shndx_count = 0;
7873 merged = FALSE;
7874 for (o = abfd->sections; o != NULL; o = o->next)
7876 struct bfd_elf_section_data *esdo = elf_section_data (o);
7877 o->reloc_count = 0;
7879 for (p = o->map_head.link_order; p != NULL; p = p->next)
7881 unsigned int reloc_count = 0;
7882 struct bfd_elf_section_data *esdi = NULL;
7883 unsigned int *rel_count1;
7885 if (p->type == bfd_section_reloc_link_order
7886 || p->type == bfd_symbol_reloc_link_order)
7887 reloc_count = 1;
7888 else if (p->type == bfd_indirect_link_order)
7890 asection *sec;
7892 sec = p->u.indirect.section;
7893 esdi = elf_section_data (sec);
7895 /* Mark all sections which are to be included in the
7896 link. This will normally be every section. We need
7897 to do this so that we can identify any sections which
7898 the linker has decided to not include. */
7899 sec->linker_mark = TRUE;
7901 if (sec->flags & SEC_MERGE)
7902 merged = TRUE;
7904 if (info->relocatable || info->emitrelocations)
7905 reloc_count = sec->reloc_count;
7906 else if (bed->elf_backend_count_relocs)
7908 Elf_Internal_Rela * relocs;
7910 relocs = _bfd_elf_link_read_relocs (abfd, sec, NULL, NULL,
7911 info->keep_memory);
7913 reloc_count = (*bed->elf_backend_count_relocs) (sec, relocs);
7915 if (elf_section_data (o)->relocs != relocs)
7916 free (relocs);
7919 if (sec->rawsize > max_contents_size)
7920 max_contents_size = sec->rawsize;
7921 if (sec->size > max_contents_size)
7922 max_contents_size = sec->size;
7924 /* We are interested in just local symbols, not all
7925 symbols. */
7926 if (bfd_get_flavour (sec->owner) == bfd_target_elf_flavour
7927 && (sec->owner->flags & DYNAMIC) == 0)
7929 size_t sym_count;
7931 if (elf_bad_symtab (sec->owner))
7932 sym_count = (elf_tdata (sec->owner)->symtab_hdr.sh_size
7933 / bed->s->sizeof_sym);
7934 else
7935 sym_count = elf_tdata (sec->owner)->symtab_hdr.sh_info;
7937 if (sym_count > max_sym_count)
7938 max_sym_count = sym_count;
7940 if (sym_count > max_sym_shndx_count
7941 && elf_symtab_shndx (sec->owner) != 0)
7942 max_sym_shndx_count = sym_count;
7944 if ((sec->flags & SEC_RELOC) != 0)
7946 size_t ext_size;
7948 ext_size = elf_section_data (sec)->rel_hdr.sh_size;
7949 if (ext_size > max_external_reloc_size)
7950 max_external_reloc_size = ext_size;
7951 if (sec->reloc_count > max_internal_reloc_count)
7952 max_internal_reloc_count = sec->reloc_count;
7957 if (reloc_count == 0)
7958 continue;
7960 o->reloc_count += reloc_count;
7962 /* MIPS may have a mix of REL and RELA relocs on sections.
7963 To support this curious ABI we keep reloc counts in
7964 elf_section_data too. We must be careful to add the
7965 relocations from the input section to the right output
7966 count. FIXME: Get rid of one count. We have
7967 o->reloc_count == esdo->rel_count + esdo->rel_count2. */
7968 rel_count1 = &esdo->rel_count;
7969 if (esdi != NULL)
7971 bfd_boolean same_size;
7972 bfd_size_type entsize1;
7974 entsize1 = esdi->rel_hdr.sh_entsize;
7975 BFD_ASSERT (entsize1 == bed->s->sizeof_rel
7976 || entsize1 == bed->s->sizeof_rela);
7977 same_size = !o->use_rela_p == (entsize1 == bed->s->sizeof_rel);
7979 if (!same_size)
7980 rel_count1 = &esdo->rel_count2;
7982 if (esdi->rel_hdr2 != NULL)
7984 bfd_size_type entsize2 = esdi->rel_hdr2->sh_entsize;
7985 unsigned int alt_count;
7986 unsigned int *rel_count2;
7988 BFD_ASSERT (entsize2 != entsize1
7989 && (entsize2 == bed->s->sizeof_rel
7990 || entsize2 == bed->s->sizeof_rela));
7992 rel_count2 = &esdo->rel_count2;
7993 if (!same_size)
7994 rel_count2 = &esdo->rel_count;
7996 /* The following is probably too simplistic if the
7997 backend counts output relocs unusually. */
7998 BFD_ASSERT (bed->elf_backend_count_relocs == NULL);
7999 alt_count = NUM_SHDR_ENTRIES (esdi->rel_hdr2);
8000 *rel_count2 += alt_count;
8001 reloc_count -= alt_count;
8004 *rel_count1 += reloc_count;
8007 if (o->reloc_count > 0)
8008 o->flags |= SEC_RELOC;
8009 else
8011 /* Explicitly clear the SEC_RELOC flag. The linker tends to
8012 set it (this is probably a bug) and if it is set
8013 assign_section_numbers will create a reloc section. */
8014 o->flags &=~ SEC_RELOC;
8017 /* If the SEC_ALLOC flag is not set, force the section VMA to
8018 zero. This is done in elf_fake_sections as well, but forcing
8019 the VMA to 0 here will ensure that relocs against these
8020 sections are handled correctly. */
8021 if ((o->flags & SEC_ALLOC) == 0
8022 && ! o->user_set_vma)
8023 o->vma = 0;
8026 if (! info->relocatable && merged)
8027 elf_link_hash_traverse (elf_hash_table (info),
8028 _bfd_elf_link_sec_merge_syms, abfd);
8030 /* Figure out the file positions for everything but the symbol table
8031 and the relocs. We set symcount to force assign_section_numbers
8032 to create a symbol table. */
8033 bfd_get_symcount (abfd) = info->strip == strip_all ? 0 : 1;
8034 BFD_ASSERT (! abfd->output_has_begun);
8035 if (! _bfd_elf_compute_section_file_positions (abfd, info))
8036 goto error_return;
8038 /* Set sizes, and assign file positions for reloc sections. */
8039 for (o = abfd->sections; o != NULL; o = o->next)
8041 if ((o->flags & SEC_RELOC) != 0)
8043 if (!(_bfd_elf_link_size_reloc_section
8044 (abfd, &elf_section_data (o)->rel_hdr, o)))
8045 goto error_return;
8047 if (elf_section_data (o)->rel_hdr2
8048 && !(_bfd_elf_link_size_reloc_section
8049 (abfd, elf_section_data (o)->rel_hdr2, o)))
8050 goto error_return;
8053 /* Now, reset REL_COUNT and REL_COUNT2 so that we can use them
8054 to count upwards while actually outputting the relocations. */
8055 elf_section_data (o)->rel_count = 0;
8056 elf_section_data (o)->rel_count2 = 0;
8059 _bfd_elf_assign_file_positions_for_relocs (abfd);
8061 /* We have now assigned file positions for all the sections except
8062 .symtab and .strtab. We start the .symtab section at the current
8063 file position, and write directly to it. We build the .strtab
8064 section in memory. */
8065 bfd_get_symcount (abfd) = 0;
8066 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
8067 /* sh_name is set in prep_headers. */
8068 symtab_hdr->sh_type = SHT_SYMTAB;
8069 /* sh_flags, sh_addr and sh_size all start off zero. */
8070 symtab_hdr->sh_entsize = bed->s->sizeof_sym;
8071 /* sh_link is set in assign_section_numbers. */
8072 /* sh_info is set below. */
8073 /* sh_offset is set just below. */
8074 symtab_hdr->sh_addralign = 1 << bed->s->log_file_align;
8076 off = elf_tdata (abfd)->next_file_pos;
8077 off = _bfd_elf_assign_file_position_for_section (symtab_hdr, off, TRUE);
8079 /* Note that at this point elf_tdata (abfd)->next_file_pos is
8080 incorrect. We do not yet know the size of the .symtab section.
8081 We correct next_file_pos below, after we do know the size. */
8083 /* Allocate a buffer to hold swapped out symbols. This is to avoid
8084 continuously seeking to the right position in the file. */
8085 if (! info->keep_memory || max_sym_count < 20)
8086 finfo.symbuf_size = 20;
8087 else
8088 finfo.symbuf_size = max_sym_count;
8089 amt = finfo.symbuf_size;
8090 amt *= bed->s->sizeof_sym;
8091 finfo.symbuf = bfd_malloc (amt);
8092 if (finfo.symbuf == NULL)
8093 goto error_return;
8094 if (elf_numsections (abfd) > SHN_LORESERVE)
8096 /* Wild guess at number of output symbols. realloc'd as needed. */
8097 amt = 2 * max_sym_count + elf_numsections (abfd) + 1000;
8098 finfo.shndxbuf_size = amt;
8099 amt *= sizeof (Elf_External_Sym_Shndx);
8100 finfo.symshndxbuf = bfd_zmalloc (amt);
8101 if (finfo.symshndxbuf == NULL)
8102 goto error_return;
8105 /* Start writing out the symbol table. The first symbol is always a
8106 dummy symbol. */
8107 if (info->strip != strip_all
8108 || emit_relocs)
8110 elfsym.st_value = 0;
8111 elfsym.st_size = 0;
8112 elfsym.st_info = 0;
8113 elfsym.st_other = 0;
8114 elfsym.st_shndx = SHN_UNDEF;
8115 if (! elf_link_output_sym (&finfo, NULL, &elfsym, bfd_und_section_ptr,
8116 NULL))
8117 goto error_return;
8120 /* Output a symbol for each section. We output these even if we are
8121 discarding local symbols, since they are used for relocs. These
8122 symbols have no names. We store the index of each one in the
8123 index field of the section, so that we can find it again when
8124 outputting relocs. */
8125 if (info->strip != strip_all
8126 || emit_relocs)
8128 elfsym.st_size = 0;
8129 elfsym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8130 elfsym.st_other = 0;
8131 for (i = 1; i < elf_numsections (abfd); i++)
8133 o = bfd_section_from_elf_index (abfd, i);
8134 if (o != NULL)
8135 o->target_index = bfd_get_symcount (abfd);
8136 elfsym.st_shndx = i;
8137 if (info->relocatable || o == NULL)
8138 elfsym.st_value = 0;
8139 else
8140 elfsym.st_value = o->vma;
8141 if (! elf_link_output_sym (&finfo, NULL, &elfsym, o, NULL))
8142 goto error_return;
8143 if (i == SHN_LORESERVE - 1)
8144 i += SHN_HIRESERVE + 1 - SHN_LORESERVE;
8148 /* Allocate some memory to hold information read in from the input
8149 files. */
8150 if (max_contents_size != 0)
8152 finfo.contents = bfd_malloc (max_contents_size);
8153 if (finfo.contents == NULL)
8154 goto error_return;
8157 if (max_external_reloc_size != 0)
8159 finfo.external_relocs = bfd_malloc (max_external_reloc_size);
8160 if (finfo.external_relocs == NULL)
8161 goto error_return;
8164 if (max_internal_reloc_count != 0)
8166 amt = max_internal_reloc_count * bed->s->int_rels_per_ext_rel;
8167 amt *= sizeof (Elf_Internal_Rela);
8168 finfo.internal_relocs = bfd_malloc (amt);
8169 if (finfo.internal_relocs == NULL)
8170 goto error_return;
8173 if (max_sym_count != 0)
8175 amt = max_sym_count * bed->s->sizeof_sym;
8176 finfo.external_syms = bfd_malloc (amt);
8177 if (finfo.external_syms == NULL)
8178 goto error_return;
8180 amt = max_sym_count * sizeof (Elf_Internal_Sym);
8181 finfo.internal_syms = bfd_malloc (amt);
8182 if (finfo.internal_syms == NULL)
8183 goto error_return;
8185 amt = max_sym_count * sizeof (long);
8186 finfo.indices = bfd_malloc (amt);
8187 if (finfo.indices == NULL)
8188 goto error_return;
8190 amt = max_sym_count * sizeof (asection *);
8191 finfo.sections = bfd_malloc (amt);
8192 if (finfo.sections == NULL)
8193 goto error_return;
8196 if (max_sym_shndx_count != 0)
8198 amt = max_sym_shndx_count * sizeof (Elf_External_Sym_Shndx);
8199 finfo.locsym_shndx = bfd_malloc (amt);
8200 if (finfo.locsym_shndx == NULL)
8201 goto error_return;
8204 if (elf_hash_table (info)->tls_sec)
8206 bfd_vma base, end = 0;
8207 asection *sec;
8209 for (sec = elf_hash_table (info)->tls_sec;
8210 sec && (sec->flags & SEC_THREAD_LOCAL);
8211 sec = sec->next)
8213 bfd_size_type size = sec->size;
8215 if (size == 0
8216 && (sec->flags & SEC_HAS_CONTENTS) == 0)
8218 struct bfd_link_order *o = sec->map_tail.link_order;
8219 if (o != NULL)
8220 size = o->offset + o->size;
8222 end = sec->vma + size;
8224 base = elf_hash_table (info)->tls_sec->vma;
8225 end = align_power (end, elf_hash_table (info)->tls_sec->alignment_power);
8226 elf_hash_table (info)->tls_size = end - base;
8229 /* Reorder SHF_LINK_ORDER sections. */
8230 for (o = abfd->sections; o != NULL; o = o->next)
8232 if (!elf_fixup_link_order (abfd, o))
8233 return FALSE;
8236 /* Since ELF permits relocations to be against local symbols, we
8237 must have the local symbols available when we do the relocations.
8238 Since we would rather only read the local symbols once, and we
8239 would rather not keep them in memory, we handle all the
8240 relocations for a single input file at the same time.
8242 Unfortunately, there is no way to know the total number of local
8243 symbols until we have seen all of them, and the local symbol
8244 indices precede the global symbol indices. This means that when
8245 we are generating relocatable output, and we see a reloc against
8246 a global symbol, we can not know the symbol index until we have
8247 finished examining all the local symbols to see which ones we are
8248 going to output. To deal with this, we keep the relocations in
8249 memory, and don't output them until the end of the link. This is
8250 an unfortunate waste of memory, but I don't see a good way around
8251 it. Fortunately, it only happens when performing a relocatable
8252 link, which is not the common case. FIXME: If keep_memory is set
8253 we could write the relocs out and then read them again; I don't
8254 know how bad the memory loss will be. */
8256 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8257 sub->output_has_begun = FALSE;
8258 for (o = abfd->sections; o != NULL; o = o->next)
8260 for (p = o->map_head.link_order; p != NULL; p = p->next)
8262 if (p->type == bfd_indirect_link_order
8263 && (bfd_get_flavour ((sub = p->u.indirect.section->owner))
8264 == bfd_target_elf_flavour)
8265 && elf_elfheader (sub)->e_ident[EI_CLASS] == bed->s->elfclass)
8267 if (! sub->output_has_begun)
8269 if (! elf_link_input_bfd (&finfo, sub))
8270 goto error_return;
8271 sub->output_has_begun = TRUE;
8274 else if (p->type == bfd_section_reloc_link_order
8275 || p->type == bfd_symbol_reloc_link_order)
8277 if (! elf_reloc_link_order (abfd, info, o, p))
8278 goto error_return;
8280 else
8282 if (! _bfd_default_link_order (abfd, info, o, p))
8283 goto error_return;
8288 /* Output any global symbols that got converted to local in a
8289 version script or due to symbol visibility. We do this in a
8290 separate step since ELF requires all local symbols to appear
8291 prior to any global symbols. FIXME: We should only do this if
8292 some global symbols were, in fact, converted to become local.
8293 FIXME: Will this work correctly with the Irix 5 linker? */
8294 eoinfo.failed = FALSE;
8295 eoinfo.finfo = &finfo;
8296 eoinfo.localsyms = TRUE;
8297 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8298 &eoinfo);
8299 if (eoinfo.failed)
8300 return FALSE;
8302 /* That wrote out all the local symbols. Finish up the symbol table
8303 with the global symbols. Even if we want to strip everything we
8304 can, we still need to deal with those global symbols that got
8305 converted to local in a version script. */
8307 /* The sh_info field records the index of the first non local symbol. */
8308 symtab_hdr->sh_info = bfd_get_symcount (abfd);
8310 if (dynamic
8311 && finfo.dynsym_sec->output_section != bfd_abs_section_ptr)
8313 Elf_Internal_Sym sym;
8314 bfd_byte *dynsym = finfo.dynsym_sec->contents;
8315 long last_local = 0;
8317 /* Write out the section symbols for the output sections. */
8318 if (info->shared || elf_hash_table (info)->is_relocatable_executable)
8320 asection *s;
8322 sym.st_size = 0;
8323 sym.st_name = 0;
8324 sym.st_info = ELF_ST_INFO (STB_LOCAL, STT_SECTION);
8325 sym.st_other = 0;
8327 for (s = abfd->sections; s != NULL; s = s->next)
8329 int indx;
8330 bfd_byte *dest;
8331 long dynindx;
8333 dynindx = elf_section_data (s)->dynindx;
8334 if (dynindx <= 0)
8335 continue;
8336 indx = elf_section_data (s)->this_idx;
8337 BFD_ASSERT (indx > 0);
8338 sym.st_shndx = indx;
8339 if (! check_dynsym (abfd, &sym))
8340 return FALSE;
8341 sym.st_value = s->vma;
8342 dest = dynsym + dynindx * bed->s->sizeof_sym;
8343 if (last_local < dynindx)
8344 last_local = dynindx;
8345 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8349 /* Write out the local dynsyms. */
8350 if (elf_hash_table (info)->dynlocal)
8352 struct elf_link_local_dynamic_entry *e;
8353 for (e = elf_hash_table (info)->dynlocal; e ; e = e->next)
8355 asection *s;
8356 bfd_byte *dest;
8358 sym.st_size = e->isym.st_size;
8359 sym.st_other = e->isym.st_other;
8361 /* Copy the internal symbol as is.
8362 Note that we saved a word of storage and overwrote
8363 the original st_name with the dynstr_index. */
8364 sym = e->isym;
8366 if (e->isym.st_shndx != SHN_UNDEF
8367 && (e->isym.st_shndx < SHN_LORESERVE
8368 || e->isym.st_shndx > SHN_HIRESERVE))
8370 s = bfd_section_from_elf_index (e->input_bfd,
8371 e->isym.st_shndx);
8373 sym.st_shndx =
8374 elf_section_data (s->output_section)->this_idx;
8375 if (! check_dynsym (abfd, &sym))
8376 return FALSE;
8377 sym.st_value = (s->output_section->vma
8378 + s->output_offset
8379 + e->isym.st_value);
8382 if (last_local < e->dynindx)
8383 last_local = e->dynindx;
8385 dest = dynsym + e->dynindx * bed->s->sizeof_sym;
8386 bed->s->swap_symbol_out (abfd, &sym, dest, 0);
8390 elf_section_data (finfo.dynsym_sec->output_section)->this_hdr.sh_info =
8391 last_local + 1;
8394 /* We get the global symbols from the hash table. */
8395 eoinfo.failed = FALSE;
8396 eoinfo.localsyms = FALSE;
8397 eoinfo.finfo = &finfo;
8398 elf_link_hash_traverse (elf_hash_table (info), elf_link_output_extsym,
8399 &eoinfo);
8400 if (eoinfo.failed)
8401 return FALSE;
8403 /* If backend needs to output some symbols not present in the hash
8404 table, do it now. */
8405 if (bed->elf_backend_output_arch_syms)
8407 typedef bfd_boolean (*out_sym_func)
8408 (void *, const char *, Elf_Internal_Sym *, asection *,
8409 struct elf_link_hash_entry *);
8411 if (! ((*bed->elf_backend_output_arch_syms)
8412 (abfd, info, &finfo, (out_sym_func) elf_link_output_sym)))
8413 return FALSE;
8416 /* Flush all symbols to the file. */
8417 if (! elf_link_flush_output_syms (&finfo, bed))
8418 return FALSE;
8420 /* Now we know the size of the symtab section. */
8421 off += symtab_hdr->sh_size;
8423 symtab_shndx_hdr = &elf_tdata (abfd)->symtab_shndx_hdr;
8424 if (symtab_shndx_hdr->sh_name != 0)
8426 symtab_shndx_hdr->sh_type = SHT_SYMTAB_SHNDX;
8427 symtab_shndx_hdr->sh_entsize = sizeof (Elf_External_Sym_Shndx);
8428 symtab_shndx_hdr->sh_addralign = sizeof (Elf_External_Sym_Shndx);
8429 amt = bfd_get_symcount (abfd) * sizeof (Elf_External_Sym_Shndx);
8430 symtab_shndx_hdr->sh_size = amt;
8432 off = _bfd_elf_assign_file_position_for_section (symtab_shndx_hdr,
8433 off, TRUE);
8435 if (bfd_seek (abfd, symtab_shndx_hdr->sh_offset, SEEK_SET) != 0
8436 || (bfd_bwrite (finfo.symshndxbuf, amt, abfd) != amt))
8437 return FALSE;
8441 /* Finish up and write out the symbol string table (.strtab)
8442 section. */
8443 symstrtab_hdr = &elf_tdata (abfd)->strtab_hdr;
8444 /* sh_name was set in prep_headers. */
8445 symstrtab_hdr->sh_type = SHT_STRTAB;
8446 symstrtab_hdr->sh_flags = 0;
8447 symstrtab_hdr->sh_addr = 0;
8448 symstrtab_hdr->sh_size = _bfd_stringtab_size (finfo.symstrtab);
8449 symstrtab_hdr->sh_entsize = 0;
8450 symstrtab_hdr->sh_link = 0;
8451 symstrtab_hdr->sh_info = 0;
8452 /* sh_offset is set just below. */
8453 symstrtab_hdr->sh_addralign = 1;
8455 off = _bfd_elf_assign_file_position_for_section (symstrtab_hdr, off, TRUE);
8456 elf_tdata (abfd)->next_file_pos = off;
8458 if (bfd_get_symcount (abfd) > 0)
8460 if (bfd_seek (abfd, symstrtab_hdr->sh_offset, SEEK_SET) != 0
8461 || ! _bfd_stringtab_emit (abfd, finfo.symstrtab))
8462 return FALSE;
8465 /* Adjust the relocs to have the correct symbol indices. */
8466 for (o = abfd->sections; o != NULL; o = o->next)
8468 if ((o->flags & SEC_RELOC) == 0)
8469 continue;
8471 elf_link_adjust_relocs (abfd, &elf_section_data (o)->rel_hdr,
8472 elf_section_data (o)->rel_count,
8473 elf_section_data (o)->rel_hashes);
8474 if (elf_section_data (o)->rel_hdr2 != NULL)
8475 elf_link_adjust_relocs (abfd, elf_section_data (o)->rel_hdr2,
8476 elf_section_data (o)->rel_count2,
8477 (elf_section_data (o)->rel_hashes
8478 + elf_section_data (o)->rel_count));
8480 /* Set the reloc_count field to 0 to prevent write_relocs from
8481 trying to swap the relocs out itself. */
8482 o->reloc_count = 0;
8485 if (dynamic && info->combreloc && dynobj != NULL)
8486 relativecount = elf_link_sort_relocs (abfd, info, &reldyn);
8488 /* If we are linking against a dynamic object, or generating a
8489 shared library, finish up the dynamic linking information. */
8490 if (dynamic)
8492 bfd_byte *dyncon, *dynconend;
8494 /* Fix up .dynamic entries. */
8495 o = bfd_get_section_by_name (dynobj, ".dynamic");
8496 BFD_ASSERT (o != NULL);
8498 dyncon = o->contents;
8499 dynconend = o->contents + o->size;
8500 for (; dyncon < dynconend; dyncon += bed->s->sizeof_dyn)
8502 Elf_Internal_Dyn dyn;
8503 const char *name;
8504 unsigned int type;
8506 bed->s->swap_dyn_in (dynobj, dyncon, &dyn);
8508 switch (dyn.d_tag)
8510 default:
8511 continue;
8512 case DT_NULL:
8513 if (relativecount > 0 && dyncon + bed->s->sizeof_dyn < dynconend)
8515 switch (elf_section_data (reldyn)->this_hdr.sh_type)
8517 case SHT_REL: dyn.d_tag = DT_RELCOUNT; break;
8518 case SHT_RELA: dyn.d_tag = DT_RELACOUNT; break;
8519 default: continue;
8521 dyn.d_un.d_val = relativecount;
8522 relativecount = 0;
8523 break;
8525 continue;
8527 case DT_INIT:
8528 name = info->init_function;
8529 goto get_sym;
8530 case DT_FINI:
8531 name = info->fini_function;
8532 get_sym:
8534 struct elf_link_hash_entry *h;
8536 h = elf_link_hash_lookup (elf_hash_table (info), name,
8537 FALSE, FALSE, TRUE);
8538 if (h != NULL
8539 && (h->root.type == bfd_link_hash_defined
8540 || h->root.type == bfd_link_hash_defweak))
8542 dyn.d_un.d_val = h->root.u.def.value;
8543 o = h->root.u.def.section;
8544 if (o->output_section != NULL)
8545 dyn.d_un.d_val += (o->output_section->vma
8546 + o->output_offset);
8547 else
8549 /* The symbol is imported from another shared
8550 library and does not apply to this one. */
8551 dyn.d_un.d_val = 0;
8553 break;
8556 continue;
8558 case DT_PREINIT_ARRAYSZ:
8559 name = ".preinit_array";
8560 goto get_size;
8561 case DT_INIT_ARRAYSZ:
8562 name = ".init_array";
8563 goto get_size;
8564 case DT_FINI_ARRAYSZ:
8565 name = ".fini_array";
8566 get_size:
8567 o = bfd_get_section_by_name (abfd, name);
8568 if (o == NULL)
8570 (*_bfd_error_handler)
8571 (_("%B: could not find output section %s"), abfd, name);
8572 goto error_return;
8574 if (o->size == 0)
8575 (*_bfd_error_handler)
8576 (_("warning: %s section has zero size"), name);
8577 dyn.d_un.d_val = o->size;
8578 break;
8580 case DT_PREINIT_ARRAY:
8581 name = ".preinit_array";
8582 goto get_vma;
8583 case DT_INIT_ARRAY:
8584 name = ".init_array";
8585 goto get_vma;
8586 case DT_FINI_ARRAY:
8587 name = ".fini_array";
8588 goto get_vma;
8590 case DT_HASH:
8591 name = ".hash";
8592 goto get_vma;
8593 case DT_STRTAB:
8594 name = ".dynstr";
8595 goto get_vma;
8596 case DT_SYMTAB:
8597 name = ".dynsym";
8598 goto get_vma;
8599 case DT_VERDEF:
8600 name = ".gnu.version_d";
8601 goto get_vma;
8602 case DT_VERNEED:
8603 name = ".gnu.version_r";
8604 goto get_vma;
8605 case DT_VERSYM:
8606 name = ".gnu.version";
8607 get_vma:
8608 o = bfd_get_section_by_name (abfd, name);
8609 if (o == NULL)
8611 (*_bfd_error_handler)
8612 (_("%B: could not find output section %s"), abfd, name);
8613 goto error_return;
8615 dyn.d_un.d_ptr = o->vma;
8616 break;
8618 case DT_REL:
8619 case DT_RELA:
8620 case DT_RELSZ:
8621 case DT_RELASZ:
8622 if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELSZ)
8623 type = SHT_REL;
8624 else
8625 type = SHT_RELA;
8626 dyn.d_un.d_val = 0;
8627 for (i = 1; i < elf_numsections (abfd); i++)
8629 Elf_Internal_Shdr *hdr;
8631 hdr = elf_elfsections (abfd)[i];
8632 if (hdr->sh_type == type
8633 && (hdr->sh_flags & SHF_ALLOC) != 0)
8635 if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
8636 dyn.d_un.d_val += hdr->sh_size;
8637 else
8639 if (dyn.d_un.d_val == 0
8640 || hdr->sh_addr < dyn.d_un.d_val)
8641 dyn.d_un.d_val = hdr->sh_addr;
8645 break;
8647 bed->s->swap_dyn_out (dynobj, &dyn, dyncon);
8651 /* If we have created any dynamic sections, then output them. */
8652 if (dynobj != NULL)
8654 if (! (*bed->elf_backend_finish_dynamic_sections) (abfd, info))
8655 goto error_return;
8657 for (o = dynobj->sections; o != NULL; o = o->next)
8659 if ((o->flags & SEC_HAS_CONTENTS) == 0
8660 || o->size == 0
8661 || o->output_section == bfd_abs_section_ptr)
8662 continue;
8663 if ((o->flags & SEC_LINKER_CREATED) == 0)
8665 /* At this point, we are only interested in sections
8666 created by _bfd_elf_link_create_dynamic_sections. */
8667 continue;
8669 if (elf_hash_table (info)->stab_info.stabstr == o)
8670 continue;
8671 if (elf_hash_table (info)->eh_info.hdr_sec == o)
8672 continue;
8673 if ((elf_section_data (o->output_section)->this_hdr.sh_type
8674 != SHT_STRTAB)
8675 || strcmp (bfd_get_section_name (abfd, o), ".dynstr") != 0)
8677 if (! bfd_set_section_contents (abfd, o->output_section,
8678 o->contents,
8679 (file_ptr) o->output_offset,
8680 o->size))
8681 goto error_return;
8683 else
8685 /* The contents of the .dynstr section are actually in a
8686 stringtab. */
8687 off = elf_section_data (o->output_section)->this_hdr.sh_offset;
8688 if (bfd_seek (abfd, off, SEEK_SET) != 0
8689 || ! _bfd_elf_strtab_emit (abfd,
8690 elf_hash_table (info)->dynstr))
8691 goto error_return;
8696 if (info->relocatable)
8698 bfd_boolean failed = FALSE;
8700 bfd_map_over_sections (abfd, bfd_elf_set_group_contents, &failed);
8701 if (failed)
8702 goto error_return;
8705 /* If we have optimized stabs strings, output them. */
8706 if (elf_hash_table (info)->stab_info.stabstr != NULL)
8708 if (! _bfd_write_stab_strings (abfd, &elf_hash_table (info)->stab_info))
8709 goto error_return;
8712 if (info->eh_frame_hdr)
8714 if (! _bfd_elf_write_section_eh_frame_hdr (abfd, info))
8715 goto error_return;
8718 if (finfo.symstrtab != NULL)
8719 _bfd_stringtab_free (finfo.symstrtab);
8720 if (finfo.contents != NULL)
8721 free (finfo.contents);
8722 if (finfo.external_relocs != NULL)
8723 free (finfo.external_relocs);
8724 if (finfo.internal_relocs != NULL)
8725 free (finfo.internal_relocs);
8726 if (finfo.external_syms != NULL)
8727 free (finfo.external_syms);
8728 if (finfo.locsym_shndx != NULL)
8729 free (finfo.locsym_shndx);
8730 if (finfo.internal_syms != NULL)
8731 free (finfo.internal_syms);
8732 if (finfo.indices != NULL)
8733 free (finfo.indices);
8734 if (finfo.sections != NULL)
8735 free (finfo.sections);
8736 if (finfo.symbuf != NULL)
8737 free (finfo.symbuf);
8738 if (finfo.symshndxbuf != NULL)
8739 free (finfo.symshndxbuf);
8740 for (o = abfd->sections; o != NULL; o = o->next)
8742 if ((o->flags & SEC_RELOC) != 0
8743 && elf_section_data (o)->rel_hashes != NULL)
8744 free (elf_section_data (o)->rel_hashes);
8747 elf_tdata (abfd)->linker = TRUE;
8749 return TRUE;
8751 error_return:
8752 if (finfo.symstrtab != NULL)
8753 _bfd_stringtab_free (finfo.symstrtab);
8754 if (finfo.contents != NULL)
8755 free (finfo.contents);
8756 if (finfo.external_relocs != NULL)
8757 free (finfo.external_relocs);
8758 if (finfo.internal_relocs != NULL)
8759 free (finfo.internal_relocs);
8760 if (finfo.external_syms != NULL)
8761 free (finfo.external_syms);
8762 if (finfo.locsym_shndx != NULL)
8763 free (finfo.locsym_shndx);
8764 if (finfo.internal_syms != NULL)
8765 free (finfo.internal_syms);
8766 if (finfo.indices != NULL)
8767 free (finfo.indices);
8768 if (finfo.sections != NULL)
8769 free (finfo.sections);
8770 if (finfo.symbuf != NULL)
8771 free (finfo.symbuf);
8772 if (finfo.symshndxbuf != NULL)
8773 free (finfo.symshndxbuf);
8774 for (o = abfd->sections; o != NULL; o = o->next)
8776 if ((o->flags & SEC_RELOC) != 0
8777 && elf_section_data (o)->rel_hashes != NULL)
8778 free (elf_section_data (o)->rel_hashes);
8781 return FALSE;
8784 /* Garbage collect unused sections. */
8786 /* The mark phase of garbage collection. For a given section, mark
8787 it and any sections in this section's group, and all the sections
8788 which define symbols to which it refers. */
8790 typedef asection * (*gc_mark_hook_fn)
8791 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
8792 struct elf_link_hash_entry *, Elf_Internal_Sym *);
8794 bfd_boolean
8795 _bfd_elf_gc_mark (struct bfd_link_info *info,
8796 asection *sec,
8797 gc_mark_hook_fn gc_mark_hook)
8799 bfd_boolean ret;
8800 bfd_boolean is_eh;
8801 asection *group_sec;
8803 sec->gc_mark = 1;
8805 /* Mark all the sections in the group. */
8806 group_sec = elf_section_data (sec)->next_in_group;
8807 if (group_sec && !group_sec->gc_mark)
8808 if (!_bfd_elf_gc_mark (info, group_sec, gc_mark_hook))
8809 return FALSE;
8811 /* Look through the section relocs. */
8812 ret = TRUE;
8813 is_eh = strcmp (sec->name, ".eh_frame") == 0;
8814 if ((sec->flags & SEC_RELOC) != 0 && sec->reloc_count > 0)
8816 Elf_Internal_Rela *relstart, *rel, *relend;
8817 Elf_Internal_Shdr *symtab_hdr;
8818 struct elf_link_hash_entry **sym_hashes;
8819 size_t nlocsyms;
8820 size_t extsymoff;
8821 bfd *input_bfd = sec->owner;
8822 const struct elf_backend_data *bed = get_elf_backend_data (input_bfd);
8823 Elf_Internal_Sym *isym = NULL;
8824 int r_sym_shift;
8826 symtab_hdr = &elf_tdata (input_bfd)->symtab_hdr;
8827 sym_hashes = elf_sym_hashes (input_bfd);
8829 /* Read the local symbols. */
8830 if (elf_bad_symtab (input_bfd))
8832 nlocsyms = symtab_hdr->sh_size / bed->s->sizeof_sym;
8833 extsymoff = 0;
8835 else
8836 extsymoff = nlocsyms = symtab_hdr->sh_info;
8838 isym = (Elf_Internal_Sym *) symtab_hdr->contents;
8839 if (isym == NULL && nlocsyms != 0)
8841 isym = bfd_elf_get_elf_syms (input_bfd, symtab_hdr, nlocsyms, 0,
8842 NULL, NULL, NULL);
8843 if (isym == NULL)
8844 return FALSE;
8847 /* Read the relocations. */
8848 relstart = _bfd_elf_link_read_relocs (input_bfd, sec, NULL, NULL,
8849 info->keep_memory);
8850 if (relstart == NULL)
8852 ret = FALSE;
8853 goto out1;
8855 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
8857 if (bed->s->arch_size == 32)
8858 r_sym_shift = 8;
8859 else
8860 r_sym_shift = 32;
8862 for (rel = relstart; rel < relend; rel++)
8864 unsigned long r_symndx;
8865 asection *rsec;
8866 struct elf_link_hash_entry *h;
8868 r_symndx = rel->r_info >> r_sym_shift;
8869 if (r_symndx == 0)
8870 continue;
8872 if (r_symndx >= nlocsyms
8873 || ELF_ST_BIND (isym[r_symndx].st_info) != STB_LOCAL)
8875 h = sym_hashes[r_symndx - extsymoff];
8876 while (h->root.type == bfd_link_hash_indirect
8877 || h->root.type == bfd_link_hash_warning)
8878 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8879 rsec = (*gc_mark_hook) (sec, info, rel, h, NULL);
8881 else
8883 rsec = (*gc_mark_hook) (sec, info, rel, NULL, &isym[r_symndx]);
8886 if (rsec && !rsec->gc_mark)
8888 if (bfd_get_flavour (rsec->owner) != bfd_target_elf_flavour)
8889 rsec->gc_mark = 1;
8890 else if (is_eh)
8891 rsec->gc_mark_from_eh = 1;
8892 else if (!_bfd_elf_gc_mark (info, rsec, gc_mark_hook))
8894 ret = FALSE;
8895 goto out2;
8900 out2:
8901 if (elf_section_data (sec)->relocs != relstart)
8902 free (relstart);
8903 out1:
8904 if (isym != NULL && symtab_hdr->contents != (unsigned char *) isym)
8906 if (! info->keep_memory)
8907 free (isym);
8908 else
8909 symtab_hdr->contents = (unsigned char *) isym;
8913 return ret;
8916 /* Sweep symbols in swept sections. Called via elf_link_hash_traverse. */
8918 struct elf_gc_sweep_symbol_info {
8919 struct bfd_link_info *info;
8920 void (*hide_symbol) (struct bfd_link_info *, struct elf_link_hash_entry *,
8921 bfd_boolean);
8924 static bfd_boolean
8925 elf_gc_sweep_symbol (struct elf_link_hash_entry *h, void *data)
8927 if (h->root.type == bfd_link_hash_warning)
8928 h = (struct elf_link_hash_entry *) h->root.u.i.link;
8930 if ((h->root.type == bfd_link_hash_defined
8931 || h->root.type == bfd_link_hash_defweak)
8932 && !h->root.u.def.section->gc_mark
8933 && !(h->root.u.def.section->owner->flags & DYNAMIC))
8935 struct elf_gc_sweep_symbol_info *inf = data;
8936 (*inf->hide_symbol) (inf->info, h, TRUE);
8939 return TRUE;
8942 /* The sweep phase of garbage collection. Remove all garbage sections. */
8944 typedef bfd_boolean (*gc_sweep_hook_fn)
8945 (bfd *, struct bfd_link_info *, asection *, const Elf_Internal_Rela *);
8947 static bfd_boolean
8948 elf_gc_sweep (bfd *abfd, struct bfd_link_info *info)
8950 bfd *sub;
8951 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
8952 gc_sweep_hook_fn gc_sweep_hook = bed->gc_sweep_hook;
8953 unsigned long section_sym_count;
8954 struct elf_gc_sweep_symbol_info sweep_info;
8956 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
8958 asection *o;
8960 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
8961 continue;
8963 for (o = sub->sections; o != NULL; o = o->next)
8965 /* Keep debug and special sections. */
8966 if ((o->flags & (SEC_DEBUGGING | SEC_LINKER_CREATED)) != 0
8967 || (o->flags & (SEC_ALLOC | SEC_LOAD)) == 0)
8968 o->gc_mark = 1;
8970 if (o->gc_mark)
8971 continue;
8973 /* Skip sweeping sections already excluded. */
8974 if (o->flags & SEC_EXCLUDE)
8975 continue;
8977 /* Since this is early in the link process, it is simple
8978 to remove a section from the output. */
8979 o->flags |= SEC_EXCLUDE;
8981 /* But we also have to update some of the relocation
8982 info we collected before. */
8983 if (gc_sweep_hook
8984 && (o->flags & SEC_RELOC) != 0
8985 && o->reloc_count > 0
8986 && !bfd_is_abs_section (o->output_section))
8988 Elf_Internal_Rela *internal_relocs;
8989 bfd_boolean r;
8991 internal_relocs
8992 = _bfd_elf_link_read_relocs (o->owner, o, NULL, NULL,
8993 info->keep_memory);
8994 if (internal_relocs == NULL)
8995 return FALSE;
8997 r = (*gc_sweep_hook) (o->owner, info, o, internal_relocs);
8999 if (elf_section_data (o)->relocs != internal_relocs)
9000 free (internal_relocs);
9002 if (!r)
9003 return FALSE;
9008 /* Remove the symbols that were in the swept sections from the dynamic
9009 symbol table. GCFIXME: Anyone know how to get them out of the
9010 static symbol table as well? */
9011 sweep_info.info = info;
9012 sweep_info.hide_symbol = bed->elf_backend_hide_symbol;
9013 elf_link_hash_traverse (elf_hash_table (info), elf_gc_sweep_symbol,
9014 &sweep_info);
9016 _bfd_elf_link_renumber_dynsyms (abfd, info, &section_sym_count);
9017 return TRUE;
9020 /* Propagate collected vtable information. This is called through
9021 elf_link_hash_traverse. */
9023 static bfd_boolean
9024 elf_gc_propagate_vtable_entries_used (struct elf_link_hash_entry *h, void *okp)
9026 if (h->root.type == bfd_link_hash_warning)
9027 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9029 /* Those that are not vtables. */
9030 if (h->vtable == NULL || h->vtable->parent == NULL)
9031 return TRUE;
9033 /* Those vtables that do not have parents, we cannot merge. */
9034 if (h->vtable->parent == (struct elf_link_hash_entry *) -1)
9035 return TRUE;
9037 /* If we've already been done, exit. */
9038 if (h->vtable->used && h->vtable->used[-1])
9039 return TRUE;
9041 /* Make sure the parent's table is up to date. */
9042 elf_gc_propagate_vtable_entries_used (h->vtable->parent, okp);
9044 if (h->vtable->used == NULL)
9046 /* None of this table's entries were referenced. Re-use the
9047 parent's table. */
9048 h->vtable->used = h->vtable->parent->vtable->used;
9049 h->vtable->size = h->vtable->parent->vtable->size;
9051 else
9053 size_t n;
9054 bfd_boolean *cu, *pu;
9056 /* Or the parent's entries into ours. */
9057 cu = h->vtable->used;
9058 cu[-1] = TRUE;
9059 pu = h->vtable->parent->vtable->used;
9060 if (pu != NULL)
9062 const struct elf_backend_data *bed;
9063 unsigned int log_file_align;
9065 bed = get_elf_backend_data (h->root.u.def.section->owner);
9066 log_file_align = bed->s->log_file_align;
9067 n = h->vtable->parent->vtable->size >> log_file_align;
9068 while (n--)
9070 if (*pu)
9071 *cu = TRUE;
9072 pu++;
9073 cu++;
9078 return TRUE;
9081 static bfd_boolean
9082 elf_gc_smash_unused_vtentry_relocs (struct elf_link_hash_entry *h, void *okp)
9084 asection *sec;
9085 bfd_vma hstart, hend;
9086 Elf_Internal_Rela *relstart, *relend, *rel;
9087 const struct elf_backend_data *bed;
9088 unsigned int log_file_align;
9090 if (h->root.type == bfd_link_hash_warning)
9091 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9093 /* Take care of both those symbols that do not describe vtables as
9094 well as those that are not loaded. */
9095 if (h->vtable == NULL || h->vtable->parent == NULL)
9096 return TRUE;
9098 BFD_ASSERT (h->root.type == bfd_link_hash_defined
9099 || h->root.type == bfd_link_hash_defweak);
9101 sec = h->root.u.def.section;
9102 hstart = h->root.u.def.value;
9103 hend = hstart + h->size;
9105 relstart = _bfd_elf_link_read_relocs (sec->owner, sec, NULL, NULL, TRUE);
9106 if (!relstart)
9107 return *(bfd_boolean *) okp = FALSE;
9108 bed = get_elf_backend_data (sec->owner);
9109 log_file_align = bed->s->log_file_align;
9111 relend = relstart + sec->reloc_count * bed->s->int_rels_per_ext_rel;
9113 for (rel = relstart; rel < relend; ++rel)
9114 if (rel->r_offset >= hstart && rel->r_offset < hend)
9116 /* If the entry is in use, do nothing. */
9117 if (h->vtable->used
9118 && (rel->r_offset - hstart) < h->vtable->size)
9120 bfd_vma entry = (rel->r_offset - hstart) >> log_file_align;
9121 if (h->vtable->used[entry])
9122 continue;
9124 /* Otherwise, kill it. */
9125 rel->r_offset = rel->r_info = rel->r_addend = 0;
9128 return TRUE;
9131 /* Mark sections containing dynamically referenced symbols. When
9132 building shared libraries, we must assume that any visible symbol is
9133 referenced. */
9135 bfd_boolean
9136 bfd_elf_gc_mark_dynamic_ref_symbol (struct elf_link_hash_entry *h, void *inf)
9138 struct bfd_link_info *info = (struct bfd_link_info *) inf;
9140 if (h->root.type == bfd_link_hash_warning)
9141 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9143 if ((h->root.type == bfd_link_hash_defined
9144 || h->root.type == bfd_link_hash_defweak)
9145 && (h->ref_dynamic
9146 || (!info->executable
9147 && h->def_regular
9148 && ELF_ST_VISIBILITY (h->other) != STV_INTERNAL
9149 && ELF_ST_VISIBILITY (h->other) != STV_HIDDEN)))
9150 h->root.u.def.section->flags |= SEC_KEEP;
9152 return TRUE;
9155 /* Do mark and sweep of unused sections. */
9157 bfd_boolean
9158 bfd_elf_gc_sections (bfd *abfd, struct bfd_link_info *info)
9160 bfd_boolean ok = TRUE;
9161 bfd *sub;
9162 asection * (*gc_mark_hook)
9163 (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
9164 struct elf_link_hash_entry *h, Elf_Internal_Sym *);
9165 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9167 if (!bed->can_gc_sections
9168 || info->relocatable
9169 || info->emitrelocations
9170 || !is_elf_hash_table (info->hash))
9172 (*_bfd_error_handler)(_("Warning: gc-sections option ignored"));
9173 return TRUE;
9176 /* Apply transitive closure to the vtable entry usage info. */
9177 elf_link_hash_traverse (elf_hash_table (info),
9178 elf_gc_propagate_vtable_entries_used,
9179 &ok);
9180 if (!ok)
9181 return FALSE;
9183 /* Kill the vtable relocations that were not used. */
9184 elf_link_hash_traverse (elf_hash_table (info),
9185 elf_gc_smash_unused_vtentry_relocs,
9186 &ok);
9187 if (!ok)
9188 return FALSE;
9190 /* Mark dynamically referenced symbols. */
9191 if (elf_hash_table (info)->dynamic_sections_created)
9192 elf_link_hash_traverse (elf_hash_table (info),
9193 bed->gc_mark_dynamic_ref,
9194 info);
9196 /* Grovel through relocs to find out who stays ... */
9197 gc_mark_hook = bed->gc_mark_hook;
9198 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9200 asection *o;
9202 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9203 continue;
9205 for (o = sub->sections; o != NULL; o = o->next)
9206 if ((o->flags & SEC_KEEP) != 0 && !o->gc_mark)
9207 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9208 return FALSE;
9211 /* ... again for sections marked from eh_frame. */
9212 for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
9214 asection *o;
9216 if (bfd_get_flavour (sub) != bfd_target_elf_flavour)
9217 continue;
9219 /* Keep .gcc_except_table.* if the associated .text.* is
9220 marked. This isn't very nice, but the proper solution,
9221 splitting .eh_frame up and using comdat doesn't pan out
9222 easily due to needing special relocs to handle the
9223 difference of two symbols in separate sections.
9224 Don't keep code sections referenced by .eh_frame. */
9225 for (o = sub->sections; o != NULL; o = o->next)
9226 if (!o->gc_mark && o->gc_mark_from_eh && (o->flags & SEC_CODE) == 0)
9228 if (strncmp (o->name, ".gcc_except_table.", 18) == 0)
9230 unsigned long len;
9231 char *fn_name;
9232 asection *fn_text;
9234 len = strlen (o->name + 18) + 1;
9235 fn_name = bfd_malloc (len + 6);
9236 if (fn_name == NULL)
9237 return FALSE;
9238 memcpy (fn_name, ".text.", 6);
9239 memcpy (fn_name + 6, o->name + 18, len);
9240 fn_text = bfd_get_section_by_name (sub, fn_name);
9241 free (fn_name);
9242 if (fn_text == NULL || !fn_text->gc_mark)
9243 continue;
9246 /* If not using specially named exception table section,
9247 then keep whatever we are using. */
9248 if (!_bfd_elf_gc_mark (info, o, gc_mark_hook))
9249 return FALSE;
9253 /* ... and mark SEC_EXCLUDE for those that go. */
9254 return elf_gc_sweep (abfd, info);
9257 /* Called from check_relocs to record the existence of a VTINHERIT reloc. */
9259 bfd_boolean
9260 bfd_elf_gc_record_vtinherit (bfd *abfd,
9261 asection *sec,
9262 struct elf_link_hash_entry *h,
9263 bfd_vma offset)
9265 struct elf_link_hash_entry **sym_hashes, **sym_hashes_end;
9266 struct elf_link_hash_entry **search, *child;
9267 bfd_size_type extsymcount;
9268 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9270 /* The sh_info field of the symtab header tells us where the
9271 external symbols start. We don't care about the local symbols at
9272 this point. */
9273 extsymcount = elf_tdata (abfd)->symtab_hdr.sh_size / bed->s->sizeof_sym;
9274 if (!elf_bad_symtab (abfd))
9275 extsymcount -= elf_tdata (abfd)->symtab_hdr.sh_info;
9277 sym_hashes = elf_sym_hashes (abfd);
9278 sym_hashes_end = sym_hashes + extsymcount;
9280 /* Hunt down the child symbol, which is in this section at the same
9281 offset as the relocation. */
9282 for (search = sym_hashes; search != sym_hashes_end; ++search)
9284 if ((child = *search) != NULL
9285 && (child->root.type == bfd_link_hash_defined
9286 || child->root.type == bfd_link_hash_defweak)
9287 && child->root.u.def.section == sec
9288 && child->root.u.def.value == offset)
9289 goto win;
9292 (*_bfd_error_handler) ("%B: %A+%lu: No symbol found for INHERIT",
9293 abfd, sec, (unsigned long) offset);
9294 bfd_set_error (bfd_error_invalid_operation);
9295 return FALSE;
9297 win:
9298 if (!child->vtable)
9300 child->vtable = bfd_zalloc (abfd, sizeof (*child->vtable));
9301 if (!child->vtable)
9302 return FALSE;
9304 if (!h)
9306 /* This *should* only be the absolute section. It could potentially
9307 be that someone has defined a non-global vtable though, which
9308 would be bad. It isn't worth paging in the local symbols to be
9309 sure though; that case should simply be handled by the assembler. */
9311 child->vtable->parent = (struct elf_link_hash_entry *) -1;
9313 else
9314 child->vtable->parent = h;
9316 return TRUE;
9319 /* Called from check_relocs to record the existence of a VTENTRY reloc. */
9321 bfd_boolean
9322 bfd_elf_gc_record_vtentry (bfd *abfd ATTRIBUTE_UNUSED,
9323 asection *sec ATTRIBUTE_UNUSED,
9324 struct elf_link_hash_entry *h,
9325 bfd_vma addend)
9327 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9328 unsigned int log_file_align = bed->s->log_file_align;
9330 if (!h->vtable)
9332 h->vtable = bfd_zalloc (abfd, sizeof (*h->vtable));
9333 if (!h->vtable)
9334 return FALSE;
9337 if (addend >= h->vtable->size)
9339 size_t size, bytes, file_align;
9340 bfd_boolean *ptr = h->vtable->used;
9342 /* While the symbol is undefined, we have to be prepared to handle
9343 a zero size. */
9344 file_align = 1 << log_file_align;
9345 if (h->root.type == bfd_link_hash_undefined)
9346 size = addend + file_align;
9347 else
9349 size = h->size;
9350 if (addend >= size)
9352 /* Oops! We've got a reference past the defined end of
9353 the table. This is probably a bug -- shall we warn? */
9354 size = addend + file_align;
9357 size = (size + file_align - 1) & -file_align;
9359 /* Allocate one extra entry for use as a "done" flag for the
9360 consolidation pass. */
9361 bytes = ((size >> log_file_align) + 1) * sizeof (bfd_boolean);
9363 if (ptr)
9365 ptr = bfd_realloc (ptr - 1, bytes);
9367 if (ptr != NULL)
9369 size_t oldbytes;
9371 oldbytes = (((h->vtable->size >> log_file_align) + 1)
9372 * sizeof (bfd_boolean));
9373 memset (((char *) ptr) + oldbytes, 0, bytes - oldbytes);
9376 else
9377 ptr = bfd_zmalloc (bytes);
9379 if (ptr == NULL)
9380 return FALSE;
9382 /* And arrange for that done flag to be at index -1. */
9383 h->vtable->used = ptr + 1;
9384 h->vtable->size = size;
9387 h->vtable->used[addend >> log_file_align] = TRUE;
9389 return TRUE;
9392 struct alloc_got_off_arg {
9393 bfd_vma gotoff;
9394 unsigned int got_elt_size;
9397 /* We need a special top-level link routine to convert got reference counts
9398 to real got offsets. */
9400 static bfd_boolean
9401 elf_gc_allocate_got_offsets (struct elf_link_hash_entry *h, void *arg)
9403 struct alloc_got_off_arg *gofarg = arg;
9405 if (h->root.type == bfd_link_hash_warning)
9406 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9408 if (h->got.refcount > 0)
9410 h->got.offset = gofarg->gotoff;
9411 gofarg->gotoff += gofarg->got_elt_size;
9413 else
9414 h->got.offset = (bfd_vma) -1;
9416 return TRUE;
9419 /* And an accompanying bit to work out final got entry offsets once
9420 we're done. Should be called from final_link. */
9422 bfd_boolean
9423 bfd_elf_gc_common_finalize_got_offsets (bfd *abfd,
9424 struct bfd_link_info *info)
9426 bfd *i;
9427 const struct elf_backend_data *bed = get_elf_backend_data (abfd);
9428 bfd_vma gotoff;
9429 unsigned int got_elt_size = bed->s->arch_size / 8;
9430 struct alloc_got_off_arg gofarg;
9432 if (! is_elf_hash_table (info->hash))
9433 return FALSE;
9435 /* The GOT offset is relative to the .got section, but the GOT header is
9436 put into the .got.plt section, if the backend uses it. */
9437 if (bed->want_got_plt)
9438 gotoff = 0;
9439 else
9440 gotoff = bed->got_header_size;
9442 /* Do the local .got entries first. */
9443 for (i = info->input_bfds; i; i = i->link_next)
9445 bfd_signed_vma *local_got;
9446 bfd_size_type j, locsymcount;
9447 Elf_Internal_Shdr *symtab_hdr;
9449 if (bfd_get_flavour (i) != bfd_target_elf_flavour)
9450 continue;
9452 local_got = elf_local_got_refcounts (i);
9453 if (!local_got)
9454 continue;
9456 symtab_hdr = &elf_tdata (i)->symtab_hdr;
9457 if (elf_bad_symtab (i))
9458 locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9459 else
9460 locsymcount = symtab_hdr->sh_info;
9462 for (j = 0; j < locsymcount; ++j)
9464 if (local_got[j] > 0)
9466 local_got[j] = gotoff;
9467 gotoff += got_elt_size;
9469 else
9470 local_got[j] = (bfd_vma) -1;
9474 /* Then the global .got entries. .plt refcounts are handled by
9475 adjust_dynamic_symbol */
9476 gofarg.gotoff = gotoff;
9477 gofarg.got_elt_size = got_elt_size;
9478 elf_link_hash_traverse (elf_hash_table (info),
9479 elf_gc_allocate_got_offsets,
9480 &gofarg);
9481 return TRUE;
9484 /* Many folk need no more in the way of final link than this, once
9485 got entry reference counting is enabled. */
9487 bfd_boolean
9488 bfd_elf_gc_common_final_link (bfd *abfd, struct bfd_link_info *info)
9490 if (!bfd_elf_gc_common_finalize_got_offsets (abfd, info))
9491 return FALSE;
9493 /* Invoke the regular ELF backend linker to do all the work. */
9494 return bfd_elf_final_link (abfd, info);
9497 bfd_boolean
9498 bfd_elf_reloc_symbol_deleted_p (bfd_vma offset, void *cookie)
9500 struct elf_reloc_cookie *rcookie = cookie;
9502 if (rcookie->bad_symtab)
9503 rcookie->rel = rcookie->rels;
9505 for (; rcookie->rel < rcookie->relend; rcookie->rel++)
9507 unsigned long r_symndx;
9509 if (! rcookie->bad_symtab)
9510 if (rcookie->rel->r_offset > offset)
9511 return FALSE;
9512 if (rcookie->rel->r_offset != offset)
9513 continue;
9515 r_symndx = rcookie->rel->r_info >> rcookie->r_sym_shift;
9516 if (r_symndx == SHN_UNDEF)
9517 return TRUE;
9519 if (r_symndx >= rcookie->locsymcount
9520 || ELF_ST_BIND (rcookie->locsyms[r_symndx].st_info) != STB_LOCAL)
9522 struct elf_link_hash_entry *h;
9524 h = rcookie->sym_hashes[r_symndx - rcookie->extsymoff];
9526 while (h->root.type == bfd_link_hash_indirect
9527 || h->root.type == bfd_link_hash_warning)
9528 h = (struct elf_link_hash_entry *) h->root.u.i.link;
9530 if ((h->root.type == bfd_link_hash_defined
9531 || h->root.type == bfd_link_hash_defweak)
9532 && elf_discarded_section (h->root.u.def.section))
9533 return TRUE;
9534 else
9535 return FALSE;
9537 else
9539 /* It's not a relocation against a global symbol,
9540 but it could be a relocation against a local
9541 symbol for a discarded section. */
9542 asection *isec;
9543 Elf_Internal_Sym *isym;
9545 /* Need to: get the symbol; get the section. */
9546 isym = &rcookie->locsyms[r_symndx];
9547 if (isym->st_shndx < SHN_LORESERVE || isym->st_shndx > SHN_HIRESERVE)
9549 isec = bfd_section_from_elf_index (rcookie->abfd, isym->st_shndx);
9550 if (isec != NULL && elf_discarded_section (isec))
9551 return TRUE;
9554 return FALSE;
9556 return FALSE;
9559 /* Discard unneeded references to discarded sections.
9560 Returns TRUE if any section's size was changed. */
9561 /* This function assumes that the relocations are in sorted order,
9562 which is true for all known assemblers. */
9564 bfd_boolean
9565 bfd_elf_discard_info (bfd *output_bfd, struct bfd_link_info *info)
9567 struct elf_reloc_cookie cookie;
9568 asection *stab, *eh;
9569 Elf_Internal_Shdr *symtab_hdr;
9570 const struct elf_backend_data *bed;
9571 bfd *abfd;
9572 unsigned int count;
9573 bfd_boolean ret = FALSE;
9575 if (info->traditional_format
9576 || !is_elf_hash_table (info->hash))
9577 return FALSE;
9579 for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next)
9581 if (bfd_get_flavour (abfd) != bfd_target_elf_flavour)
9582 continue;
9584 bed = get_elf_backend_data (abfd);
9586 if ((abfd->flags & DYNAMIC) != 0)
9587 continue;
9589 eh = bfd_get_section_by_name (abfd, ".eh_frame");
9590 if (info->relocatable
9591 || (eh != NULL
9592 && (eh->size == 0
9593 || bfd_is_abs_section (eh->output_section))))
9594 eh = NULL;
9596 stab = bfd_get_section_by_name (abfd, ".stab");
9597 if (stab != NULL
9598 && (stab->size == 0
9599 || bfd_is_abs_section (stab->output_section)
9600 || stab->sec_info_type != ELF_INFO_TYPE_STABS))
9601 stab = NULL;
9603 if (stab == NULL
9604 && eh == NULL
9605 && bed->elf_backend_discard_info == NULL)
9606 continue;
9608 symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
9609 cookie.abfd = abfd;
9610 cookie.sym_hashes = elf_sym_hashes (abfd);
9611 cookie.bad_symtab = elf_bad_symtab (abfd);
9612 if (cookie.bad_symtab)
9614 cookie.locsymcount = symtab_hdr->sh_size / bed->s->sizeof_sym;
9615 cookie.extsymoff = 0;
9617 else
9619 cookie.locsymcount = symtab_hdr->sh_info;
9620 cookie.extsymoff = symtab_hdr->sh_info;
9623 if (bed->s->arch_size == 32)
9624 cookie.r_sym_shift = 8;
9625 else
9626 cookie.r_sym_shift = 32;
9628 cookie.locsyms = (Elf_Internal_Sym *) symtab_hdr->contents;
9629 if (cookie.locsyms == NULL && cookie.locsymcount != 0)
9631 cookie.locsyms = bfd_elf_get_elf_syms (abfd, symtab_hdr,
9632 cookie.locsymcount, 0,
9633 NULL, NULL, NULL);
9634 if (cookie.locsyms == NULL)
9635 return FALSE;
9638 if (stab != NULL)
9640 cookie.rels = NULL;
9641 count = stab->reloc_count;
9642 if (count != 0)
9643 cookie.rels = _bfd_elf_link_read_relocs (abfd, stab, NULL, NULL,
9644 info->keep_memory);
9645 if (cookie.rels != NULL)
9647 cookie.rel = cookie.rels;
9648 cookie.relend = cookie.rels;
9649 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9650 if (_bfd_discard_section_stabs (abfd, stab,
9651 elf_section_data (stab)->sec_info,
9652 bfd_elf_reloc_symbol_deleted_p,
9653 &cookie))
9654 ret = TRUE;
9655 if (elf_section_data (stab)->relocs != cookie.rels)
9656 free (cookie.rels);
9660 if (eh != NULL)
9662 cookie.rels = NULL;
9663 count = eh->reloc_count;
9664 if (count != 0)
9665 cookie.rels = _bfd_elf_link_read_relocs (abfd, eh, NULL, NULL,
9666 info->keep_memory);
9667 cookie.rel = cookie.rels;
9668 cookie.relend = cookie.rels;
9669 if (cookie.rels != NULL)
9670 cookie.relend += count * bed->s->int_rels_per_ext_rel;
9672 if (_bfd_elf_discard_section_eh_frame (abfd, info, eh,
9673 bfd_elf_reloc_symbol_deleted_p,
9674 &cookie))
9675 ret = TRUE;
9677 if (cookie.rels != NULL
9678 && elf_section_data (eh)->relocs != cookie.rels)
9679 free (cookie.rels);
9682 if (bed->elf_backend_discard_info != NULL
9683 && (*bed->elf_backend_discard_info) (abfd, &cookie, info))
9684 ret = TRUE;
9686 if (cookie.locsyms != NULL
9687 && symtab_hdr->contents != (unsigned char *) cookie.locsyms)
9689 if (! info->keep_memory)
9690 free (cookie.locsyms);
9691 else
9692 symtab_hdr->contents = (unsigned char *) cookie.locsyms;
9696 if (info->eh_frame_hdr
9697 && !info->relocatable
9698 && _bfd_elf_discard_section_eh_frame_hdr (output_bfd, info))
9699 ret = TRUE;
9701 return ret;
9704 void
9705 _bfd_elf_section_already_linked (bfd *abfd, struct bfd_section * sec)
9707 flagword flags;
9708 const char *name, *p;
9709 struct bfd_section_already_linked *l;
9710 struct bfd_section_already_linked_hash_entry *already_linked_list;
9711 asection *group;
9713 /* A single member comdat group section may be discarded by a
9714 linkonce section. See below. */
9715 if (sec->output_section == bfd_abs_section_ptr)
9716 return;
9718 flags = sec->flags;
9720 /* Check if it belongs to a section group. */
9721 group = elf_sec_group (sec);
9723 /* Return if it isn't a linkonce section nor a member of a group. A
9724 comdat group section also has SEC_LINK_ONCE set. */
9725 if ((flags & SEC_LINK_ONCE) == 0 && group == NULL)
9726 return;
9728 if (group)
9730 /* If this is the member of a single member comdat group, check if
9731 the group should be discarded. */
9732 if (elf_next_in_group (sec) == sec
9733 && (group->flags & SEC_LINK_ONCE) != 0)
9734 sec = group;
9735 else
9736 return;
9739 /* FIXME: When doing a relocatable link, we may have trouble
9740 copying relocations in other sections that refer to local symbols
9741 in the section being discarded. Those relocations will have to
9742 be converted somehow; as of this writing I'm not sure that any of
9743 the backends handle that correctly.
9745 It is tempting to instead not discard link once sections when
9746 doing a relocatable link (technically, they should be discarded
9747 whenever we are building constructors). However, that fails,
9748 because the linker winds up combining all the link once sections
9749 into a single large link once section, which defeats the purpose
9750 of having link once sections in the first place.
9752 Also, not merging link once sections in a relocatable link
9753 causes trouble for MIPS ELF, which relies on link once semantics
9754 to handle the .reginfo section correctly. */
9756 name = bfd_get_section_name (abfd, sec);
9758 if (strncmp (name, ".gnu.linkonce.", sizeof (".gnu.linkonce.") - 1) == 0
9759 && (p = strchr (name + sizeof (".gnu.linkonce.") - 1, '.')) != NULL)
9760 p++;
9761 else
9762 p = name;
9764 already_linked_list = bfd_section_already_linked_table_lookup (p);
9766 for (l = already_linked_list->entry; l != NULL; l = l->next)
9768 /* We may have 3 different sections on the list: group section,
9769 comdat section and linkonce section. SEC may be a linkonce or
9770 group section. We match a group section with a group section,
9771 a linkonce section with a linkonce section, and ignore comdat
9772 section. */
9773 if ((flags & SEC_GROUP) == (l->sec->flags & SEC_GROUP)
9774 && strcmp (name, l->sec->name) == 0
9775 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL)
9777 /* The section has already been linked. See if we should
9778 issue a warning. */
9779 switch (flags & SEC_LINK_DUPLICATES)
9781 default:
9782 abort ();
9784 case SEC_LINK_DUPLICATES_DISCARD:
9785 break;
9787 case SEC_LINK_DUPLICATES_ONE_ONLY:
9788 (*_bfd_error_handler)
9789 (_("%B: ignoring duplicate section `%A'"),
9790 abfd, sec);
9791 break;
9793 case SEC_LINK_DUPLICATES_SAME_SIZE:
9794 if (sec->size != l->sec->size)
9795 (*_bfd_error_handler)
9796 (_("%B: duplicate section `%A' has different size"),
9797 abfd, sec);
9798 break;
9800 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
9801 if (sec->size != l->sec->size)
9802 (*_bfd_error_handler)
9803 (_("%B: duplicate section `%A' has different size"),
9804 abfd, sec);
9805 else if (sec->size != 0)
9807 bfd_byte *sec_contents, *l_sec_contents;
9809 if (!bfd_malloc_and_get_section (abfd, sec, &sec_contents))
9810 (*_bfd_error_handler)
9811 (_("%B: warning: could not read contents of section `%A'"),
9812 abfd, sec);
9813 else if (!bfd_malloc_and_get_section (l->sec->owner, l->sec,
9814 &l_sec_contents))
9815 (*_bfd_error_handler)
9816 (_("%B: warning: could not read contents of section `%A'"),
9817 l->sec->owner, l->sec);
9818 else if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
9819 (*_bfd_error_handler)
9820 (_("%B: warning: duplicate section `%A' has different contents"),
9821 abfd, sec);
9823 if (sec_contents)
9824 free (sec_contents);
9825 if (l_sec_contents)
9826 free (l_sec_contents);
9828 break;
9831 /* Set the output_section field so that lang_add_section
9832 does not create a lang_input_section structure for this
9833 section. Since there might be a symbol in the section
9834 being discarded, we must retain a pointer to the section
9835 which we are really going to use. */
9836 sec->output_section = bfd_abs_section_ptr;
9837 sec->kept_section = l->sec;
9839 if (flags & SEC_GROUP)
9841 asection *first = elf_next_in_group (sec);
9842 asection *s = first;
9844 while (s != NULL)
9846 s->output_section = bfd_abs_section_ptr;
9847 /* Record which group discards it. */
9848 s->kept_section = l->sec;
9849 s = elf_next_in_group (s);
9850 /* These lists are circular. */
9851 if (s == first)
9852 break;
9856 return;
9860 if (group)
9862 /* If this is the member of a single member comdat group and the
9863 group hasn't be discarded, we check if it matches a linkonce
9864 section. We only record the discarded comdat group. Otherwise
9865 the undiscarded group will be discarded incorrectly later since
9866 itself has been recorded. */
9867 for (l = already_linked_list->entry; l != NULL; l = l->next)
9868 if ((l->sec->flags & SEC_GROUP) == 0
9869 && bfd_coff_get_comdat_section (l->sec->owner, l->sec) == NULL
9870 && bfd_elf_match_symbols_in_sections (l->sec,
9871 elf_next_in_group (sec)))
9873 elf_next_in_group (sec)->output_section = bfd_abs_section_ptr;
9874 elf_next_in_group (sec)->kept_section = l->sec;
9875 group->output_section = bfd_abs_section_ptr;
9876 break;
9878 if (l == NULL)
9879 return;
9881 else
9882 /* There is no direct match. But for linkonce section, we should
9883 check if there is a match with comdat group member. We always
9884 record the linkonce section, discarded or not. */
9885 for (l = already_linked_list->entry; l != NULL; l = l->next)
9886 if (l->sec->flags & SEC_GROUP)
9888 asection *first = elf_next_in_group (l->sec);
9890 if (first != NULL
9891 && elf_next_in_group (first) == first
9892 && bfd_elf_match_symbols_in_sections (first, sec))
9894 sec->output_section = bfd_abs_section_ptr;
9895 sec->kept_section = l->sec;
9896 break;
9900 /* This is the first section with this name. Record it. */
9901 bfd_section_already_linked_table_insert (already_linked_list, sec);
9904 bfd_boolean
9905 _bfd_elf_common_definition (Elf_Internal_Sym *sym)
9907 return sym->st_shndx == SHN_COMMON;
9910 unsigned int
9911 _bfd_elf_common_section_index (asection *sec ATTRIBUTE_UNUSED)
9913 return SHN_COMMON;
9916 asection *
9917 _bfd_elf_common_section (asection *sec ATTRIBUTE_UNUSED)
9919 return bfd_com_section_ptr;